Medical instruments including wrists with hybrid redirect surfaces

ABSTRACT

Certain aspects relate to medical instruments including wrists with hybrid redirect surfaces. Such medical instruments can include, for example, a shaft with a wrist positioned at a distal end. The wrist can include a proximal clevis connected to the shaft and a distal clevis pivotally connected to the proximal clevis. The wrist can also include a static redirect surface, such as a face of a clevis, and a dynamic redirect surface, such as a pulley. The instrument can include an end effector connected to the distal clevis. A plurality of pull wires can extend through the shaft and the wrist and engage with and actuate the wrist and the end effector. A first pull wire segment of the plurality of pull wires can engage the static redirect surface, and a second pull wire segment of the plurality of pull wires can engage the dynamic redirect surface.

PRIORITY APPLICATION

This application claims priority to U.S. Provisional Application No.62/868,808, filed Jun. 28, 2019, which is incorporated herein byreference in its entirety and for all purposes. Any and all applicationsfor which a foreign or domestic priority claim is identified in theApplication Data Sheet as filed with the present application are herebyincorporated by reference under 37 CFR 1.57.

TECHNICAL FIELD

The systems and methods disclosed herein relate to medical instruments,and more particularly to medical instruments including wrists withhybrid redirect surfaces. The medical instruments including wrists withhybrid redirect surfaces can be implemented on robotic medical systems.

BACKGROUND

Medical procedures, such as laparoscopy, may involve accessing andvisualizing an internal region of a patient. In a laparoscopicprocedure, a medical instrument can be inserted into an internal regionthrough a laparoscopic access port.

In certain procedures, a robotically-enabled medical system may be usedto control the insertion and/or manipulation of the medical instrumentand an end effector thereof. The end effector can be connected to anelongated shaft of the medical instrument by an articulable wrist. Therobotically-enabled medical system may also include a robotic arm orother instrument positioning device. The robotically-enabled medicalsystem may also include a controller used to control the positioning ofthe medical instrument during the procedure.

SUMMARY

The systems, methods and devices of this disclosure each have severalinnovative aspects, no single one of which is solely responsible for thedesirable attributes disclosed herein.

This application is directed to medical instruments having a novel wristarchitecture that utilizes hybrid redirect surfaces, in which at leastone redirect surface is stationary and at least one other isnon-stationary.

In a first aspect, a medical instrument includes: a shaft extendingbetween a proximal end and a distal end; a wrist positioned at thedistal end of the shaft, the wrist comprising a proximal clevisconnected to the distal end of the shaft, a distal clevis pivotallyconnected to the proximal clevis, the distal clevis configured to rotateabout a pitch axis, a plurality of proximal pulleys configured to rotateabout the pitch axis, and a plurality of distal pulleys configured torotate about a yaw axis; and an end effector connected to the pluralityof distal pulleys; a plurality of pull wires engaged with the pluralityof proximal pulleys and the plurality of distal pulleys and configuredto articulate the wrist and actuate the end effector, wherein theplurality of pull wires comprise at least a first pull wire segmenthaving a first cable path length extending between a first proximalpulley of the plurality of proximal pulleys and a first distal pulley ofthe plurality of distal pulleys, and a second pull wire segment having asecond cable path length extending between a second proximal pulley ofthe plurality of proximal pulleys and the first distal pulley, whereinthe first cable path length is less than the second cable path length.

The medical instrument can include one or more of the followingfeatures, in any combination: (a) wherein the end effector comprises afirst jaw member connected to the first distal pulley, and a second jawmember connected to a second distal pulley of the plurality of distalpulleys; (b) wherein actuation of the first pull wire segment causesrotation of the first jaw member in a first direction to open the endeffector; (c) wherein actuation of the second pull wire segment causesrotation of the second jaw member in a second direction to close the endeffector; (d) wherein the first pull wire segment extends between thefirst proximal pulley and the first distal pulley without contacting thedistal clevis; (e) wherein the first pull wire segment extendssubstantially parallel to a longitudinal axis of the wrist; (f) whereinthe first pull wire segment extends at an angle of less than 10 degreesrelative to a longitudinal axis of the wrist; (g) wherein the secondpull wire segment contacts a redirect surface of the distal clevisbetween the second proximal pulley and the first distal pulley; (h)wherein the redirect surface comprises a static surface of the distalclevis; (i) a conductive cable extending through the wrist to the endeffector, wherein the conductive cable is configured to extend over asecond redirect surface of the distal clevis; (j) wherein the secondredirect surface of the distal clevis comprises a support leg of thedistal clevis; (k) wherein the support leg is positioned between atleast two of the plurality of proximal pulleys; (l) wherein theconductive cable is coupled to the first pull wire segment; and/or (m)wherein the end effector comprises a bipolar end effector and theconductive cable is coupled to a jaw member of the end effector toenergize the jaw member.

In a second aspect, a medical instrument includes: a shaft extendingbetween a proximal end and a distal end; a wrist positioned at thedistal end of the shaft, the wrist comprising a proximal clevisconnected to the distal end of the shaft, a distal clevis pivotallyconnected to the proximal clevis, the distal clevis configured to rotateabout a pitch axis, a plurality of proximal pulleys configured to rotateabout the pitch axis, and a plurality of distal pulleys configured torotate about a yaw axis; and an end effector connected to the pluralityof distal pulleys; a plurality of pull wires engaged with the pluralityof proximal pulleys and the plurality of distal pulleys and configuredto articulate the wrist and actuate the end effector, wherein theplurality of pull wires comprise at least a first pull wire segmentextending between a first proximal pulley of the plurality of proximalpulleys and a first distal pulley of the plurality of distal pulleyswithout contacting the distal clevis, and a second pull wire segmentextending between a second proximal pulley of the plurality of proximalpulleys and the first distal pulley, the second pull wire segmentcontacting a redirect surface of the distal clevis.

The medical instrument can include one or more of the followingfeatures, in any combination: (a) wherein the end effector comprises afirst jaw member connected to the first distal pulley, and a second jawmember connected to a second distal pulley of the plurality of distalpulleys; (b) wherein actuation of the first pull wire segment causesrotation of the first jaw member in a first direction to open the endeffector; (c) wherein actuation of the second pull wire segment causesrotation of the second jaw member in a second direction to close the endeffector; (d) wherein the first pull wire segment extends substantiallyparallel to a longitudinal axis of the wrist; (e) wherein the first pullwire segment extends at an angle of less than 10 degrees relative to alongitudinal axis of the wrist; (f) wherein the redirect surfacecomprises a static surface of the distal clevis; (g) wherein the firstpull wire segment comprises a first cable path length extending betweenthe first proximal pulley and the first distal pulley, and the secondpull wire segment comprises a second cable path length extending betweenthe second proximal pulley and the first distal pulley, wherein thefirst cable path length is less than the second cable path length; (h) aconductive cable extending through the wrist to the end effector,wherein the conductive cable is configured to extend over a secondredirect surface of the distal clevis; (i) wherein the second redirectsurface of the distal clevis comprises a support leg of the distalclevis; (j) wherein the support leg is positioned between at least twoof the plurality of proximal pulleys; (k) wherein the conductive cableis coupled to the first pull wire segment; and/or (l) wherein the endeffector comprises a bipolar end effector and the conductive cable iscoupled to a jaw member of the end effector to energize the jaw member.

In another aspect, a medical instrument includes: a shaft extendingbetween a proximal end and a distal end; a wrist positioned at thedistal end of the shaft, the wrist comprising a proximal clevisconnected to the distal end of the shaft, a distal clevis pivotallyconnected to the proximal clevis, the distal clevis configured to rotateabout a pitch axis, a plurality of proximal pulleys configured to rotateabout the pitch axis, and a plurality of distal pulleys configured torotate about a yaw axis; and an end effector connected to the pluralityof distal pulleys; a plurality of pull wires engaged with the pluralityof proximal pulleys and the plurality of distal pulleys and configuredto articulate the wrist and actuate the end effector; and a conductivecable extending through the wrist to the end effector, wherein theconductive cable is configured to extend over a redirect surface of thedistal clevis.

The medical instrument can include one or more of the followingfeatures, in any combination: (a) wherein the redirect surface of thedistal clevis comprises a support leg of the distal clevis; (b) whereinthe support leg is positioned between at least two of the plurality ofproximal pulleys; (c) wherein the conductive cable extends over aredirect surface of the proximal clevis; (d) wherein the conductivecable is coupled to the first pull wire segment; (e) wherein the endeffector comprises a bipolar end effector and the conductive cable iscoupled to a jaw member of the end effector to energize the jaw member;(f) wherein the end effector comprises a first jaw member connected tothe first distal pulley, and a second jaw member connected to a seconddistal pulley of the plurality of distal pulleys; (g) wherein actuationof the first pull wire segment causes rotation of the first jaw memberin a first direction to open the end effector; (h) wherein actuation ofthe second pull wire segment causes rotation of the second jaw member ina second direction to close the end effector; (i) wherein the first pullwire segment extends substantially parallel to a longitudinal axis ofthe wrist; (j) wherein the first pull wire segment extends at an angleof less than 10 degrees relative to a longitudinal axis of the wrist;and/or (k) wherein the first pull wire segment comprises a first cablepath length extending between the first proximal pulley and the firstdistal pulley, and the second pull wire segment comprises a second cablepath length extending between the second proximal pulley and the firstdistal pulley, wherein the first cable path length is less than thesecond cable path length.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosed aspects will hereinafter be described in conjunction withthe appended drawings, provided to illustrate and not to limit thedisclosed aspects, wherein like designations denote like elements.

FIG. 1 illustrates an embodiment of a cart-based robotic system arrangedfor diagnostic and/or therapeutic bronchoscopy.

FIG. 2 depicts further aspects of the robotic system of FIG. 1.

FIG. 3 illustrates an embodiment of the robotic system of FIG. 1arranged for ureteroscopy.

FIG. 4 illustrates an embodiment of the robotic system of FIG. 1arranged for a vascular procedure.

FIG. 5 illustrates an embodiment of a table-based robotic systemarranged for a bronchoscopic procedure.

FIG. 6 provides an alternative view of the robotic system of FIG. 5.

FIG. 7 illustrates an example system configured to stow robotic arm(s).

FIG. 8 illustrates an embodiment of a table-based robotic systemconfigured for a ureteroscopic procedure.

FIG. 9 illustrates an embodiment of a table-based robotic systemconfigured for a laparoscopic procedure.

FIG. 10 illustrates an embodiment of the table-based robotic system ofFIGS. 5-9 with pitch or tilt adjustment.

FIG. 11 provides a detailed illustration of the interface between thetable and the column of the table-based robotic system of FIGS. 5-10.

FIG. 12 illustrates an alternative embodiment of a table-based roboticsystem.

FIG. 13 illustrates an end view of the table-based robotic system ofFIG. 12.

FIG. 14 illustrates an end view of a table-based robotic system withrobotic arms attached thereto.

FIG. 15 illustrates an exemplary instrument driver.

FIG. 16 illustrates an exemplary medical instrument with a pairedinstrument driver.

FIG. 17 illustrates an alternative design for an instrument driver andinstrument where the axes of the drive units are parallel to the axis ofthe elongated shaft of the instrument.

FIG. 18 illustrates an instrument having an instrument-based insertionarchitecture.

FIG. 19 illustrates an exemplary controller.

FIG. 20 depicts a block diagram illustrating a localization system thatestimates a location of one or more elements of the robotic systems ofFIGS. 1-10, such as the location of the instrument of FIGS. 16-18, inaccordance to an example embodiment.

FIG. 21 is a side view of an embodiment of a medical instrumentincluding an end effector connected to a shaft of the medical instrumentby a wrist.

FIG. 22 is a perspective view of an embodiment of an end effector andwrist of a medical instrument that includes static redirect surfaces inthe wrist.

FIGS. 23A-23E illustrate an embodiment of a medical instrument includinga wrist with hybrid redirect surfaces.

FIG. 23A is a perspective view of the medical instrument.

FIG. 23B is a perspective view of the medical instrument with a distalclevis illustrated as transparent so as to show static redirectsurfaces.

FIG. 23C is a is a first side view of the medical instrument.

FIG. 23D is a second side view of the medical instrument.

FIG. 23E is a top view of a proximal clevis of the medical instrument.

FIG. 24 illustrates an embodiment of a distal pulley, jaw member, andpull wire of a medical instrument.

FIG. 25A illustrate an alternative embodiment of a distal clevis thatincludes hybrid redirect surfaces.

FIG. 25B illustrates an example cable path along static and dynamicredirect surfaces for the distal clevis of FIG. 25A.

FIG. 26A illustrates an example of distal clevis that includes fourdynamic redirect surfaces

FIG. 26B illustrates another view of the distal clevis of FIG. 26A.

FIG. 27A is a perspective view of another embodiment of a medicalinstrument.

FIG. 27B shows a perspective view of the medical instrument of FIG. 27Awith a distal clevis illustrated as transparent.

FIG. 28 is a cross-sectional view of the medical instrument of FIG. 27A.

FIG. 29 is a top view of the medical instrument of FIG. 27A.

FIGS. 30A and 30B are views illustrating proximal and distal pulleys ofthe medical instrument of FIG. 27A.

FIG. 31 is a first side view of the medical instrument of FIG. 27A.

FIG. 32 is a second side view of the medical instrument of FIG. 27A.

FIG. 33 is a cross-sectional side view of the medical instrument of FIG.27A.

FIG. 34 is a cross-sectional view of the medical instrument of FIG. 27A,illustrating shaft redirect pulleys thereof.

FIG. 35 is a diagram illustrating an example cable path length of themedical instrument of FIG. 27A.

DETAILED DESCRIPTION 1. Overview

Aspects of the present disclosure may be integrated into arobotically-enabled medical system capable of performing a variety ofmedical procedures, including both minimally invasive, such aslaparoscopy, and non-invasive, such as endoscopy, procedures. Amongendoscopic procedures, the system may be capable of performingbronchoscopy, ureteroscopy, gastroscopy, etc.

In addition to performing the breadth of procedures, the system mayprovide additional benefits, such as enhanced imaging and guidance toassist the physician. Additionally, the system may provide the physicianwith the ability to perform the procedure from an ergonomic positionwithout the need for awkward arm motions and positions. Still further,the system may provide the physician with the ability to perform theprocedure with improved ease of use such that one or more of theinstruments of the system can be controlled by a single user.

Various embodiments will be described below in conjunction with thedrawings for purposes of illustration. It should be appreciated thatmany other implementations of the disclosed concepts are possible, andvarious advantages can be achieved with the disclosed implementations.Headings are included herein for reference and to aid in locatingvarious sections. These headings are not intended to limit the scope ofthe concepts described with respect thereto. Such concepts may haveapplicability throughout the entire specification.

A. Robotic System—Cart.

The robotically-enabled medical system may be configured in a variety ofways depending on the particular procedure. FIG. 1 illustrates anembodiment of a cart-based robotically-enabled system 10 arranged for adiagnostic and/or therapeutic bronchoscopy. During a bronchoscopy, thesystem 10 may comprise a cart 11 having one or more robotic arms 12 todeliver a medical instrument, such as a steerable endoscope 13, whichmay be a procedure-specific bronchoscope for bronchoscopy, to a naturalorifice access point (i.e., the mouth of the patient positioned on atable in the present example) to deliver diagnostic and/or therapeutictools. As shown, the cart 11 may be positioned proximate to thepatient's upper torso in order to provide access to the access point.Similarly, the robotic arms 12 may be actuated to position thebronchoscope relative to the access point. The arrangement in FIG. 1 mayalso be utilized when performing a gastro-intestinal (GI) procedure witha gastroscope, a specialized endoscope for GI procedures. FIG. 2 depictsan example embodiment of the cart in greater detail.

With continued reference to FIG. 1, once the cart 11 is properlypositioned, the robotic arms 12 may insert the steerable endoscope 13into the patient robotically, manually, or a combination thereof. Asshown, the steerable endoscope 13 may comprise at least two telescopingparts, such as an inner leader portion and an outer sheath portion, eachportion coupled to a separate instrument driver from the set ofinstrument drivers 28, each instrument driver coupled to the distal endof an individual robotic arm. This linear arrangement of the instrumentdrivers 28, which facilitates coaxially aligning the leader portion withthe sheath portion, creates a “virtual rail” 29 that may be repositionedin space by manipulating the one or more robotic arms 12 into differentangles and/or positions. The virtual rails described herein are depictedin the Figures using dashed lines, and accordingly the dashed lines donot depict any physical structure of the system. Translation of theinstrument drivers 28 along the virtual rail 29 telescopes the innerleader portion relative to the outer sheath portion or advances orretracts the endoscope 13 from the patient. The angle of the virtualrail 29 may be adjusted, translated, and pivoted based on clinicalapplication or physician preference. For example, in bronchoscopy, theangle and position of the virtual rail 29 as shown represents acompromise between providing physician access to the endoscope 13 whileminimizing friction that results from bending the endoscope 13 into thepatient's mouth.

The endoscope 13 may be directed down the patient's trachea and lungsafter insertion using precise commands from the robotic system untilreaching the target destination or operative site. In order to enhancenavigation through the patient's lung network and/or reach the desiredtarget, the endoscope 13 may be manipulated to telescopically extend theinner leader portion from the outer sheath portion to obtain enhancedarticulation and greater bend radius. The use of separate instrumentdrivers 28 also allows the leader portion and sheath portion to bedriven independently of each other.

For example, the endoscope 13 may be directed to deliver a biopsy needleto a target, such as, for example, a lesion or nodule within the lungsof a patient. The needle may be deployed down a working channel thatruns the length of the endoscope to obtain a tissue sample to beanalyzed by a pathologist. Depending on the pathology results,additional tools may be deployed down the working channel of theendoscope for additional biopsies. After identifying a nodule to bemalignant, the endoscope 13 may endoscopically deliver tools to resectthe potentially cancerous tissue. In some instances, diagnostic andtherapeutic treatments can be delivered in separate procedures. In thosecircumstances, the endoscope 13 may also be used to deliver a fiducialto “mark” the location of the target nodule as well. In other instances,diagnostic and therapeutic treatments may be delivered during the sameprocedure.

The system 10 may also include a movable tower 30, which may beconnected via support cables to the cart 11 to provide support forcontrols, electronics, fluidics, optics, sensors, and/or power to thecart 11. Placing such functionality in the tower 30 allows for a smallerform factor cart 11 that may be more easily adjusted and/orre-positioned by an operating physician and his/her staff. Additionally,the division of functionality between the cart/table and the supporttower 30 reduces operating room clutter and facilitates improvingclinical workflow. While the cart 11 may be positioned close to thepatient, the tower 30 may be stowed in a remote location to stay out ofthe way during a procedure.

In support of the robotic systems described above, the tower 30 mayinclude component(s) of a computer-based control system that storescomputer program instructions, for example, within a non-transitorycomputer-readable storage medium such as a persistent magnetic storagedrive, solid state drive, etc. The execution of those instructions,whether the execution occurs in the tower 30 or the cart 11, may controlthe entire system or sub-system(s) thereof. For example, when executedby a processor of the computer system, the instructions may cause thecomponents of the robotics system to actuate the relevant carriages andarm mounts, actuate the robotics arms, and control the medicalinstruments. For example, in response to receiving the control signal,the motors in the joints of the robotics arms may position the arms intoa certain posture.

The tower 30 may also include a pump, flow meter, valve control, and/orfluid access in order to provide controlled irrigation and aspirationcapabilities to the system that may be deployed through the endoscope13. These components may also be controlled using the computer system ofthe tower 30. In some embodiments, irrigation and aspirationcapabilities may be delivered directly to the endoscope 13 throughseparate cable(s).

The tower 30 may include a voltage and surge protector designed toprovide filtered and protected electrical power to the cart 11, therebyavoiding placement of a power transformer and other auxiliary powercomponents in the cart 11, resulting in a smaller, more moveable cart11.

The tower 30 may also include support equipment for the sensors deployedthroughout the robotic system 10. For example, the tower 30 may includeoptoelectronics equipment for detecting, receiving, and processing datareceived from the optical sensors or cameras throughout the roboticsystem 10. In combination with the control system, such optoelectronicsequipment may be used to generate real-time images for display in anynumber of consoles deployed throughout the system, including in thetower 30. Similarly, the tower 30 may also include an electronicsubsystem for receiving and processing signals received from deployedelectromagnetic (EM) sensors. The tower 30 may also be used to house andposition an EM field generator for detection by EM sensors in or on themedical instrument.

The tower 30 may also include a console 31 in addition to other consolesavailable in the rest of the system, e.g., console mounted on top of thecart. The console 31 may include a user interface and a display screen,such as a touchscreen, for the physician operator. Consoles in thesystem 10 are generally designed to provide both robotic controls aswell as preoperative and real-time information of the procedure, such asnavigational and localization information of the endoscope 13. When theconsole 31 is not the only console available to the physician, it may beused by a second operator, such as a nurse, to monitor the health orvitals of the patient and the operation of the system 10, as well as toprovide procedure-specific data, such as navigational and localizationinformation. In other embodiments, the console 30 is housed in a bodythat is separate from the tower 30.

The tower 30 may be coupled to the cart 11 and endoscope 13 through oneor more cables or connections (not shown). In some embodiments, thesupport functionality from the tower 30 may be provided through a singlecable to the cart 11, simplifying and de-cluttering the operating room.In other embodiments, specific functionality may be coupled in separatecabling and connections. For example, while power may be providedthrough a single power cable to the cart 11, the support for controls,optics, fluidics, and/or navigation may be provided through a separatecable.

FIG. 2 provides a detailed illustration of an embodiment of the cart 11from the cart-based robotically-enabled system shown in FIG. 1. The cart11 generally includes an elongated support structure 14 (often referredto as a “column”), a cart base 15, and a console 16 at the top of thecolumn 14. The column 14 may include one or more carriages, such as acarriage 17 (alternatively “arm support”) for supporting the deploymentof one or more robotic arms 12 (three shown in FIG. 2). The carriage 17may include individually configurable arm mounts that rotate along aperpendicular axis to adjust the base of the robotic arms 12 for betterpositioning relative to the patient. The carriage 17 also includes acarriage interface 19 that allows the carriage 17 to verticallytranslate along the column 14.

The carriage interface 19 is connected to the column 14 through slots,such as slot 20, that are positioned on opposite sides of the column 14to guide the vertical translation of the carriage 17. The slot 20contains a vertical translation interface to position and hold thecarriage 17 at various vertical heights relative to the cart base 15.Vertical translation of the carriage 17 allows the cart 11 to adjust thereach of the robotic arms 12 to meet a variety of table heights, patientsizes, and physician preferences. Similarly, the individuallyconfigurable arm mounts on the carriage 17 allow the robotic arm base 21of the robotic arms 12 to be angled in a variety of configurations.

In some embodiments, the slot 20 may be supplemented with slot coversthat are flush and parallel to the slot surface to prevent dirt andfluid ingress into the internal chambers of the column 14 and thevertical translation interface as the carriage 17 vertically translates.The slot covers may be deployed through pairs of spring spoolspositioned near the vertical top and bottom of the slot 20. The coversare coiled within the spools until deployed to extend and retract fromtheir coiled state as the carriage 17 vertically translates up and down.The spring-loading of the spools provides force to retract the coverinto a spool when the carriage 17 translates towards the spool, whilealso maintaining a tight seal when the carriage 17 translates away fromthe spool. The covers may be connected to the carriage 17 using, forexample, brackets in the carriage interface 19 to ensure properextension and retraction of the cover as the carriage 17 translates.

The column 14 may internally comprise mechanisms, such as gears andmotors, that are designed to use a vertically aligned lead screw totranslate the carriage 17 in a mechanized fashion in response to controlsignals generated in response to user inputs, e.g., inputs from theconsole 16.

The robotic arms 12 may generally comprise robotic arm bases 21 and endeffectors 22, separated by a series of linkages 23 that are connected bya series of joints 24, each joint comprising an independent actuator,each actuator comprising an independently controllable motor. Eachindependently controllable joint represents an independent degree offreedom available to the robotic arm 12. Each of the robotic arms 12 mayhave seven joints, and thus provide seven degrees of freedom. Amultitude of joints result in a multitude of degrees of freedom,allowing for “redundant” degrees of freedom. Having redundant degrees offreedom allows the robotic arms 12 to position their respective endeffectors 22 at a specific position, orientation, and trajectory inspace using different linkage positions and joint angles. This allowsfor the system to position and direct a medical instrument from adesired point in space while allowing the physician to move the armjoints into a clinically advantageous position away from the patient tocreate greater access, while avoiding arm collisions.

The cart base 15 balances the weight of the column 14, carriage 17, androbotic arms 12 over the floor. Accordingly, the cart base 15 housesheavier components, such as electronics, motors, power supply, as wellas components that either enable movement and/or immobilize the cart 11.For example, the cart base 15 includes rollable wheel-shaped casters 25that allow for the cart 11 to easily move around the room prior to aprocedure. After reaching the appropriate position, the casters 25 maybe immobilized using wheel locks to hold the cart 11 in place during theprocedure.

Positioned at the vertical end of the column 14, the console 16 allowsfor both a user interface for receiving user input and a display screen(or a dual-purpose device such as, for example, a touchscreen 26) toprovide the physician user with both preoperative and intraoperativedata. Potential preoperative data on the touchscreen 26 may includepreoperative plans, navigation and mapping data derived frompreoperative computerized tomography (CT) scans, and/or notes frompreoperative patient interviews. Intraoperative data on display mayinclude optical information provided from the tool, sensor andcoordinate information from sensors, as well as vital patientstatistics, such as respiration, heart rate, and/or pulse. The console16 may be positioned and tilted to allow a physician to access theconsole 16 from the side of the column 14 opposite the carriage 17. Fromthis position, the physician may view the console 16, robotic arms 12,and patient while operating the console 16 from behind the cart 11. Asshown, the console 16 also includes a handle 27 to assist withmaneuvering and stabilizing the cart 11.

FIG. 3 illustrates an embodiment of a robotically-enabled system 10arranged for ureteroscopy. In a ureteroscopic procedure, the cart 11 maybe positioned to deliver a ureteroscope 32, a procedure-specificendoscope designed to traverse a patient's urethra and ureter, to thelower abdominal area of the patient. In a ureteroscopy, it may bedesirable for the ureteroscope 32 to be directly aligned with thepatient's urethra to reduce friction and forces on the sensitive anatomyin the area. As shown, the cart 11 may be aligned at the foot of thetable to allow the robotic arms 12 to position the ureteroscope 32 fordirect linear access to the patient's urethra. From the foot of thetable, the robotic arms 12 may insert the ureteroscope 32 along thevirtual rail 33 directly into the patient's lower abdomen through theurethra.

After insertion into the urethra, using similar control techniques as inbronchoscopy, the ureteroscope 32 may be navigated into the bladder,ureters, and/or kidneys for diagnostic and/or therapeutic applications.For example, the ureteroscope 32 may be directed into the ureter andkidneys to break up kidney stone build up using a laser or ultrasoniclithotripsy device deployed down the working channel of the ureteroscope32. After lithotripsy is complete, the resulting stone fragments may beremoved using baskets deployed down the ureteroscope 32.

FIG. 4 illustrates an embodiment of a robotically-enabled system 10similarly arranged for a vascular procedure. In a vascular procedure,the system 10 may be configured such that the cart 11 may deliver amedical instrument 34, such as a steerable catheter, to an access pointin the femoral artery in the patient's leg. The femoral artery presentsboth a larger diameter for navigation as well as a relatively lesscircuitous and tortuous path to the patient's heart, which simplifiesnavigation. As in a ureteroscopic procedure, the cart 11 may bepositioned towards the patient's legs and lower abdomen to allow therobotic arms 12 to provide a virtual rail 35 with direct linear accessto the femoral artery access point in the patient's thigh/hip region.After insertion into the artery, the medical instrument 34 may bedirected and inserted by translating the instrument drivers 28.Alternatively, the cart may be positioned around the patient's upperabdomen in order to reach alternative vascular access points, such as,for example, the carotid and brachial arteries near the shoulder andwrist.

B. Robotic System—Table.

Embodiments of the robotically-enabled medical system may alsoincorporate the patient's table. Incorporation of the table reduces theamount of capital equipment within the operating room by removing thecart, which allows greater access to the patient. FIG. 5 illustrates anembodiment of such a robotically-enabled system arranged for abronchoscopic procedure. System 36 includes a support structure orcolumn 37 for supporting platform 38 (shown as a “table” or “bed”) overthe floor. Much like in the cart-based systems, the end effectors of therobotic arms 39 of the system 36 comprise instrument drivers 42 that aredesigned to manipulate an elongated medical instrument, such as abronchoscope 40 in FIG. 5, through or along a virtual rail 41 formedfrom the linear alignment of the instrument drivers 42. In practice, aC-arm for providing fluoroscopic imaging may be positioned over thepatient's upper abdominal area by placing the emitter and detectoraround the table 38.

FIG. 6 provides an alternative view of the system 36 without the patientand medical instrument for discussion purposes. As shown, the column 37may include one or more carriages 43 shown as ring-shaped in the system36, from which the one or more robotic arms 39 may be based. Thecarriages 43 may translate along a vertical column interface 44 thatruns the length of the column 37 to provide different vantage pointsfrom which the robotic arms 39 may be positioned to reach the patient.The carriage(s) 43 may rotate around the column 37 using a mechanicalmotor positioned within the column 37 to allow the robotic arms 39 tohave access to multiples sides of the table 38, such as, for example,both sides of the patient. In embodiments with multiple carriages, thecarriages may be individually positioned on the column and may translateand/or rotate independently of the other carriages. While the carriages43 need not surround the column 37 or even be circular, the ring-shapeas shown facilitates rotation of the carriages 43 around the column 37while maintaining structural balance. Rotation and translation of thecarriages 43 allows the system 36 to align the medical instruments, suchas endoscopes and laparoscopes, into different access points on thepatient. In other embodiments (not shown), the system 36 can include apatient table or bed with adjustable arm supports in the form of bars orrails extending alongside it. One or more robotic arms 39 (e.g., via ashoulder with an elbow joint) can be attached to the adjustable armsupports, which can be vertically adjusted. By providing verticaladjustment, the robotic arms 39 are advantageously capable of beingstowed compactly beneath the patient table or bed, and subsequentlyraised during a procedure.

The robotic arms 39 may be mounted on the carriages 43 through a set ofarm mounts 45 comprising a series of joints that may individually rotateand/or telescopically extend to provide additional configurability tothe robotic arms 39. Additionally, the arm mounts 45 may be positionedon the carriages 43 such that, when the carriages 43 are appropriatelyrotated, the arm mounts 45 may be positioned on either the same side ofthe table 38 (as shown in FIG. 6), on opposite sides of the table 38 (asshown in FIG. 9), or on adjacent sides of the table 38 (not shown).

The column 37 structurally provides support for the table 38, and a pathfor vertical translation of the carriages 43. Internally, the column 37may be equipped with lead screws for guiding vertical translation of thecarriages, and motors to mechanize the translation of the carriages 43based the lead screws. The column 37 may also convey power and controlsignals to the carriages 43 and the robotic arms 39 mounted thereon.

The table base 46 serves a similar function as the cart base 15 in thecart 11 shown in FIG. 2, housing heavier components to balance thetable/bed 38, the column 37, the carriages 43, and the robotic arms 39.The table base 46 may also incorporate rigid casters to providestability during procedures. Deployed from the bottom of the table base46, the casters may extend in opposite directions on both sides of thebase 46 and retract when the system 36 needs to be moved.

With continued reference to FIG. 6, the system 36 may also include atower (not shown) that divides the functionality of the system 36between the table and the tower to reduce the form factor and bulk ofthe table. As in earlier disclosed embodiments, the tower may provide avariety of support functionalities to the table, such as processing,computing, and control capabilities, power, fluidics, and/or optical andsensor processing. The tower may also be movable to be positioned awayfrom the patient to improve physician access and de-clutter theoperating room. Additionally, placing components in the tower allows formore storage space in the table base 46 for potential stowage of therobotic arms 39. The tower may also include a master controller orconsole that provides both a user interface for user input, such askeyboard and/or pendant, as well as a display screen (or touchscreen)for preoperative and intraoperative information, such as real-timeimaging, navigation, and tracking information. In some embodiments, thetower may also contain holders for gas tanks to be used forinsufflation.

In some embodiments, a table base may stow and store the robotic armswhen not in use. FIG. 7 illustrates a system 47 that stows robotic armsin an embodiment of the table-based system. In the system 47, carriages48 may be vertically translated into base 49 to stow robotic arms 50,arm mounts 51, and the carriages 48 within the base 49. Base covers 52may be translated and retracted open to deploy the carriages 48, armmounts 51, and robotic arms 50 around column 53, and closed to stow toprotect them when not in use. The base covers 52 may be sealed with amembrane 54 along the edges of its opening to prevent dirt and fluidingress when closed.

FIG. 8 illustrates an embodiment of a robotically-enabled table-basedsystem configured for a ureteroscopic procedure. In a ureteroscopy, thetable 38 may include a swivel portion 55 for positioning a patientoff-angle from the column 37 and table base 46. The swivel portion 55may rotate or pivot around a pivot point (e.g., located below thepatient's head) in order to position the bottom portion of the swivelportion 55 away from the column 37. For example, the pivoting of theswivel portion 55 allows a C-arm (not shown) to be positioned over thepatient's lower abdomen without competing for space with the column (notshown) below table 38. By rotating the carriage 35 (not shown) aroundthe column 37, the robotic arms 39 may directly insert a ureteroscope 56along a virtual rail 57 into the patient's groin area to reach theurethra. In a ureteroscopy, stirrups 58 may also be fixed to the swivelportion 55 of the table 38 to support the position of the patient's legsduring the procedure and allow clear access to the patient's groin area.

In a laparoscopic procedure, through small incision(s) in the patient'sabdominal wall, minimally invasive instruments may be inserted into thepatient's anatomy. In some embodiments, the minimally invasiveinstruments comprise an elongated rigid member, such as a shaft, whichis used to access anatomy within the patient. After inflation of thepatient's abdominal cavity, the instruments may be directed to performsurgical or medical tasks, such as grasping, cutting, ablating,suturing, etc. In some embodiments, the instruments can comprise ascope, such as a laparoscope. FIG. 9 illustrates an embodiment of arobotically-enabled table-based system configured for a laparoscopicprocedure. As shown in FIG. 9, the carriages 43 of the system 36 may berotated and vertically adjusted to position pairs of the robotic arms 39on opposite sides of the table 38, such that instrument 59 may bepositioned using the arm mounts 45 to be passed through minimalincisions on both sides of the patient to reach his/her abdominalcavity.

To accommodate laparoscopic procedures, the robotically-enabled tablesystem may also tilt the platform to a desired angle. FIG. 10illustrates an embodiment of the robotically-enabled medical system withpitch or tilt adjustment. As shown in FIG. 10, the system 36 mayaccommodate tilt of the table 38 to position one portion of the table ata greater distance from the floor than the other. Additionally, the armmounts 45 may rotate to match the tilt such that the robotic arms 39maintain the same planar relationship with the table 38. To accommodatesteeper angles, the column 37 may also include telescoping portions 60that allow vertical extension of the column 37 to keep the table 38 fromtouching the floor or colliding with the table base 46.

FIG. 11 provides a detailed illustration of the interface between thetable 38 and the column 37. Pitch rotation mechanism 61 may beconfigured to alter the pitch angle of the table 38 relative to thecolumn 37 in multiple degrees of freedom. The pitch rotation mechanism61 may be enabled by the positioning of orthogonal axes 1, 2 at thecolumn-table interface, each axis actuated by a separate motor 3, 4responsive to an electrical pitch angle command. Rotation along onescrew 5 would enable tilt adjustments in one axis 1, while rotationalong the other screw 6 would enable tilt adjustments along the otheraxis 2. In some embodiments, a ball joint can be used to alter the pitchangle of the table 38 relative to the column 37 in multiple degrees offreedom.

For example, pitch adjustments are particularly useful when trying toposition the table in a Trendelenburg position, i.e., position thepatient's lower abdomen at a higher position from the floor than thepatient's upper abdomen, for lower abdominal surgery. The Trendelenburgposition causes the patient's internal organs to slide towards his/herupper abdomen through the force of gravity, clearing out the abdominalcavity for minimally invasive tools to enter and perform lower abdominalsurgical or medical procedures, such as laparoscopic prostatectomy.

FIGS. 12 and 13 illustrate isometric and end views of an alternativeembodiment of a table-based surgical robotics system 100. The surgicalrobotics system 100 includes one or more adjustable arm supports 105that can be configured to support one or more robotic arms (see, forexample, FIG. 14) relative to a table 101. In the illustratedembodiment, a single adjustable arm support 105 is shown, though anadditional arm support can be provided on an opposite side of the table101. The adjustable arm support 105 can be configured so that it canmove relative to the table 101 to adjust and/or vary the position of theadjustable arm support 105 and/or any robotic arms mounted theretorelative to the table 101. For example, the adjustable arm support 105may be adjusted one or more degrees of freedom relative to the table101. The adjustable arm support 105 provides high versatility to thesystem 100, including the ability to easily stow the one or moreadjustable arm supports 105 and any robotics arms attached theretobeneath the table 101. The adjustable arm support 105 can be elevatedfrom the stowed position to a position below an upper surface of thetable 101. In other embodiments, the adjustable arm support 105 can beelevated from the stowed position to a position above an upper surfaceof the table 101.

The adjustable arm support 105 can provide several degrees of freedom,including lift, lateral translation, tilt, etc. In the illustratedembodiment of FIGS. 12 and 13, the arm support 105 is configured withfour degrees of freedom, which are illustrated with arrows in FIG. 12. Afirst degree of freedom allows for adjustment of the adjustable armsupport 105 in the z-direction (“Z-lift”). For example, the adjustablearm support 105 can include a carriage 109 configured to move up or downalong or relative to a column 102 supporting the table 101. A seconddegree of freedom can allow the adjustable arm support 105 to tilt. Forexample, the adjustable arm support 105 can include a rotary joint,which can allow the adjustable arm support 105 to be aligned with thebed in a Trendelenburg position. A third degree of freedom can allow theadjustable arm support 105 to “pivot up,” which can be used to adjust adistance between a side of the table 101 and the adjustable arm support105. A fourth degree of freedom can permit translation of the adjustablearm support 105 along a longitudinal length of the table.

The surgical robotics system 100 in FIGS. 12 and 13 can comprise a tablesupported by a column 102 that is mounted to a base 103. The base 103and the column 102 support the table 101 relative to a support surface.A floor axis 131 and a support axis 133 are shown in FIG. 13.

The adjustable arm support 105 can be mounted to the column 102. Inother embodiments, the arm support 105 can be mounted to the table 101or base 103. The adjustable arm support 105 can include a carriage 109,a bar or rail connector 111 and a bar or rail 107. In some embodiments,one or more robotic arms mounted to the rail 107 can translate and moverelative to one another.

The carriage 109 can be attached to the column 102 by a first joint 113,which allows the carriage 109 to move relative to the column 102 (e.g.,such as up and down a first or vertical axis 123). The first joint 113can provide the first degree of freedom (“Z-lift”) to the adjustable armsupport 105. The adjustable arm support 105 can include a second joint115, which provides the second degree of freedom (tilt) for theadjustable arm support 105. The adjustable arm support 105 can include athird joint 117, which can provide the third degree of freedom (“pivotup”) for the adjustable arm support 105. An additional joint 119 (shownin FIG. 13) can be provided that mechanically constrains the third joint117 to maintain an orientation of the rail 107 as the rail connector 111is rotated about a third axis 127. The adjustable arm support 105 caninclude a fourth joint 121, which can provide a fourth degree of freedom(translation) for the adjustable arm support 105 along a fourth axis129.

FIG. 14 illustrates an end view of the surgical robotics system 140Awith two adjustable arm supports 105A, 105B mounted on opposite sides ofa table 101. A first robotic arm 142A is attached to the bar or rail107A of the first adjustable arm support 105B. The first robotic arm142A includes a base 144A attached to the rail 107A. The distal end ofthe first robotic arm 142A includes an instrument drive mechanism 146Athat can attach to one or more robotic medical instruments or tools.Similarly, the second robotic arm 142B includes a base 144B attached tothe rail 107B. The distal end of the second robotic arm 142B includes aninstrument drive mechanism 146B. The instrument drive mechanism 146B canbe configured to attach to one or more robotic medical instruments ortools.

In some embodiments, one or more of the robotic arms 142A, 142Bcomprises an arm with seven or more degrees of freedom. In someembodiments, one or more of the robotic arms 142A, 142B can includeeight degrees of freedom, including an insertion axis (1-degree offreedom including insertion), a wrist (3-degrees of freedom includingwrist pitch, yaw and roll), an elbow (1-degree of freedom includingelbow pitch), a shoulder (2-degrees of freedom including shoulder pitchand yaw), and base 144A, 144B (1-degree of freedom includingtranslation). In some embodiments, the insertion degree of freedom canbe provided by the robotic arm 142A, 142B, while in other embodiments,the instrument itself provides insertion via an instrument-basedinsertion architecture.

C. Instrument Driver & Interface.

The end effectors of the system's robotic arms may comprise (i) aninstrument driver (alternatively referred to as “instrument drivemechanism” or “instrument device manipulator”) that incorporateselectro-mechanical means for actuating the medical instrument and (ii) aremovable or detachable medical instrument, which may be devoid of anyelectro-mechanical components, such as motors. This dichotomy may bedriven by the need to sterilize medical instruments used in medicalprocedures, and the inability to adequately sterilize expensive capitalequipment due to their intricate mechanical assemblies and sensitiveelectronics. Accordingly, the medical instruments may be designed to bedetached, removed, and interchanged from the instrument driver (and thusthe system) for individual sterilization or disposal by the physician orthe physician's staff. In contrast, the instrument drivers need not bechanged or sterilized, and may be draped for protection.

FIG. 15 illustrates an example instrument driver. Positioned at thedistal end of a robotic arm, instrument driver 62 comprises one or moredrive units 63 arranged with parallel axes to provide controlled torqueto a medical instrument via drive shafts 64. Each drive unit 63comprises an individual drive shaft 64 for interacting with theinstrument, a gear head 65 for converting the motor shaft rotation to adesired torque, a motor 66 for generating the drive torque, an encoder67 to measure the speed of the motor shaft and provide feedback to thecontrol circuitry, and control circuitry 68 for receiving controlsignals and actuating the drive unit. Each drive unit 63 beingindependently controlled and motorized, the instrument driver 62 mayprovide multiple (e.g., four as shown in FIG. 15) independent driveoutputs to the medical instrument. In operation, the control circuitry68 would receive a control signal, transmit a motor signal to the motor66, compare the resulting motor speed as measured by the encoder 67 withthe desired speed, and modulate the motor signal to generate the desiredtorque.

For procedures that require a sterile environment, the robotic systemmay incorporate a drive interface, such as a sterile adapter connectedto a sterile drape, that sits between the instrument driver and themedical instrument. The chief purpose of the sterile adapter is totransfer angular motion from the drive shafts of the instrument driverto the drive inputs of the instrument while maintaining physicalseparation, and thus sterility, between the drive shafts and driveinputs. Accordingly, an example sterile adapter may comprise a series ofrotational inputs and outputs intended to be mated with the drive shaftsof the instrument driver and drive inputs on the instrument. Connectedto the sterile adapter, the sterile drape, comprised of a thin, flexiblematerial such as transparent or translucent plastic, is designed tocover the capital equipment, such as the instrument driver, robotic arm,and cart (in a cart-based system) or table (in a table-based system).Use of the drape would allow the capital equipment to be positionedproximate to the patient while still being located in an area notrequiring sterilization (i.e., non-sterile field). On the other side ofthe sterile drape, the medical instrument may interface with the patientin an area requiring sterilization (i.e., sterile field).

D. Medical Instrument.

FIG. 16 illustrates an example medical instrument with a pairedinstrument driver. Like other instruments designed for use with arobotic system, medical instrument 70 comprises an elongated shaft 71(or elongate body) and an instrument base 72. The instrument base 72,also referred to as an “instrument handle” due to its intended designfor manual interaction by the physician, may generally compriserotatable drive inputs 73, e.g., receptacles, pulleys or spools, thatare designed to be mated with drive outputs 74 that extend through adrive interface on instrument driver 75 at the distal end of robotic arm76. When physically connected, latched, and/or coupled, the mated driveinputs 73 of the instrument base 72 may share axes of rotation with thedrive outputs 74 in the instrument driver 75 to allow the transfer oftorque from the drive outputs 74 to the drive inputs 73. In someembodiments, the drive outputs 74 may comprise splines that are designedto mate with receptacles on the drive inputs 73.

The elongated shaft 71 is designed to be delivered through either ananatomical opening or lumen, e.g., as in endoscopy, or a minimallyinvasive incision, e.g., as in laparoscopy. The elongated shaft 71 maybe either flexible (e.g., having properties similar to an endoscope) orrigid (e.g., having properties similar to a laparoscope) or contain acustomized combination of both flexible and rigid portions. Whendesigned for laparoscopy, the distal end of a rigid elongated shaft maybe connected to an end effector extending from a jointed wrist formedfrom a clevis with at least one degree of freedom and a surgical tool ormedical instrument, such as, for example, a grasper or scissors, thatmay be actuated based on force from the tendons as the drive inputsrotate in response to torque received from the drive outputs 74 of theinstrument driver 75. When designed for endoscopy, the distal end of aflexible elongated shaft may include a steerable or controllable bendingsection that may be articulated and bent based on torque received fromthe drive outputs 74 of the instrument driver 75.

Torque from the instrument driver 75 is transmitted down the elongatedshaft 71 using tendons along the elongated shaft 71. These individualtendons, such as pull wires, may be individually anchored to individualdrive inputs 73 within the instrument handle 72. From the handle 72, thetendons are directed down one or more pull lumens along the elongatedshaft 71 and anchored at the distal portion of the elongated shaft 71,or in the wrist at the distal portion of the elongated shaft. During asurgical procedure, such as a laparoscopic, endoscopic or hybridprocedure, these tendons may be coupled to a distally mounted endeffector, such as a wrist, grasper, or scissor. Under such anarrangement, torque exerted on drive inputs 73 would transfer tension tothe tendon, thereby causing the end effector to actuate in some way. Insome embodiments, during a surgical procedure, the tendon may cause ajoint to rotate about an axis, thereby causing the end effector to movein one direction or another. Alternatively, the tendon may be connectedto one or more jaws of a grasper at the distal end of the elongatedshaft 71, where tension from the tendon causes the grasper to close.

In endoscopy, the tendons may be coupled to a bending or articulatingsection positioned along the elongated shaft 71 (e.g., at the distalend) via adhesive, control ring, or other mechanical fixation. Whenfixedly attached to the distal end of a bending section, torque exertedon the drive inputs 73 would be transmitted down the tendons, causingthe softer, bending section (sometimes referred to as the articulablesection or region) to bend or articulate. Along the non-bendingsections, it may be advantageous to spiral or helix the individual pulllumens that direct the individual tendons along (or inside) the walls ofthe endoscope shaft to balance the radial forces that result fromtension in the pull wires. The angle of the spiraling and/or spacingtherebetween may be altered or engineered for specific purposes, whereintighter spiraling exhibits lesser shaft compression under load forces,while lower amounts of spiraling results in greater shaft compressionunder load forces, but limits bending. On the other end of the spectrum,the pull lumens may be directed parallel to the longitudinal axis of theelongated shaft 71 to allow for controlled articulation in the desiredbending or articulable sections.

In endoscopy, the elongated shaft 71 houses a number of components toassist with the robotic procedure. The shaft 71 may comprise a workingchannel for deploying surgical tools (or medical instruments),irrigation, and/or aspiration to the operative region at the distal endof the shaft 71. The shaft 71 may also accommodate wires and/or opticalfibers to transfer signals to/from an optical assembly at the distaltip, which may include an optical camera. The shaft 71 may alsoaccommodate optical fibers to carry light from proximally-located lightsources, such as light emitting diodes, to the distal end of the shaft71.

At the distal end of the instrument 70, the distal tip may also comprisethe opening of a working channel for delivering tools for diagnosticand/or therapy, irrigation, and aspiration to an operative site. Thedistal tip may also include a port for a camera, such as a fiberscope ora digital camera, to capture images of an internal anatomical space.Relatedly, the distal tip may also include ports for light sources forilluminating the anatomical space when using the camera.

In the example of FIG. 16, the drive shaft axes, and thus the driveinput axes, are orthogonal to the axis of the elongated shaft 71. Thisarrangement, however, complicates roll capabilities for the elongatedshaft 71. Rolling the elongated shaft 71 along its axis while keepingthe drive inputs 73 static results in undesirable tangling of thetendons as they extend off the drive inputs 73 and enter pull lumenswithin the elongated shaft 71. The resulting entanglement of suchtendons may disrupt any control algorithms intended to predict movementof the flexible elongated shaft 71 during an endoscopic procedure.

FIG. 17 illustrates an alternative design for an instrument driver andinstrument where the axes of the drive units are parallel to the axis ofthe elongated shaft of the instrument. As shown, a circular instrumentdriver 80 comprises four drive units with their drive outputs 81 alignedin parallel at the end of a robotic arm 82. The drive units, and theirrespective drive outputs 81, are housed in a rotational assembly 83 ofthe instrument driver 80 that is driven by one of the drive units withinthe assembly 83. In response to torque provided by the rotational driveunit, the rotational assembly 83 rotates along a circular bearing thatconnects the rotational assembly 83 to the non-rotational portion 84 ofthe instrument driver 80. Power and controls signals may be communicatedfrom the non-rotational portion 84 of the instrument driver 80 to therotational assembly 83 through electrical contacts that may bemaintained through rotation by a brushed slip ring connection (notshown). In other embodiments, the rotational assembly 83 may beresponsive to a separate drive unit that is integrated into thenon-rotatable portion 84, and thus not in parallel to the other driveunits. The rotational mechanism 83 allows the instrument driver 80 torotate the drive units, and their respective drive outputs 81, as asingle unit around an instrument driver axis 85.

Like earlier disclosed embodiments, an instrument 86 may comprise anelongated shaft portion 88 and an instrument base 87 (shown with atransparent external skin for discussion purposes) comprising aplurality of drive inputs 89 (such as receptacles, pulleys, and spools)that are configured to receive the drive outputs 81 in the instrumentdriver 80. Unlike prior disclosed embodiments, the instrument shaft 88extends from the center of the instrument base 87 with an axissubstantially parallel to the axes of the drive inputs 89, rather thanorthogonal as in the design of FIG. 16.

When coupled to the rotational assembly 83 of the instrument driver 80,the medical instrument 86, comprising instrument base 87 and instrumentshaft 88, rotates in combination with the rotational assembly 83 aboutthe instrument driver axis 85. Since the instrument shaft 88 ispositioned at the center of instrument base 87, the instrument shaft 88is coaxial with instrument driver axis 85 when attached. Thus, rotationof the rotational assembly 83 causes the instrument shaft 88 to rotateabout its own longitudinal axis. Moreover, as the instrument base 87rotates with the instrument shaft 88, any tendons connected to the driveinputs 89 in the instrument base 87 are not tangled during rotation.Accordingly, the parallelism of the axes of the drive outputs 81, driveinputs 89, and instrument shaft 88 allows for the shaft rotation withouttangling any control tendons.

FIG. 18 illustrates an instrument having an instrument based insertionarchitecture in accordance with some embodiments. The instrument 150 canbe coupled to any of the instrument drivers discussed above. Theinstrument 150 comprises an elongated shaft 152, an end effector 162connected to the shaft 152, and a handle 170 coupled to the shaft 152.The elongated shaft 152 comprises a tubular member having a proximalportion 154 and a distal portion 156. The elongated shaft 152 comprisesone or more channels or grooves 158 along its outer surface. The grooves158 are configured to receive one or more wires or cables 180therethrough. One or more cables 180 thus run along an outer surface ofthe elongated shaft 152. In other embodiments, cables 180 can also runthrough the elongated shaft 152. Manipulation of the one or more cables180 (e.g., via an instrument driver) results in actuation of the endeffector 162.

The instrument handle 170, which may also be referred to as aninstrument base, may generally comprise an attachment interface 172having one or more mechanical inputs 174, e.g., receptacles, pulleys orspools, that are designed to be reciprocally mated with one or moretorque couplers on an attachment surface of an instrument driver. Insome embodiments, the instrument 150 comprises a series of pulleys orcables that enable the elongated shaft 152 to translate relative to thehandle 170. In other words, the instrument 150 itself comprises aninstrument-based insertion architecture that accommodates insertion ofthe instrument, thereby minimizing the reliance on a robot arm toprovide insertion of the instrument 150. In other embodiments, a roboticarm can be largely responsible for instrument insertion.

E. Controller.

Any of the robotic systems described herein can include an input deviceor controller for manipulating an instrument attached to a robotic arm.In some embodiments, the controller can be coupled (e.g.,communicatively, electronically, electrically, wirelessly and/ormechanically) with an instrument such that manipulation of thecontroller causes a corresponding manipulation of the instrument e.g.,via master slave control.

FIG. 19 is a perspective view of an embodiment of a controller 182. Inthe present embodiment, the controller 182 comprises a hybrid controllerthat can have both impedance and admittance control. In otherembodiments, the controller 182 can utilize just impedance or passivecontrol. In other embodiments, the controller 182 can utilize justadmittance control. By being a hybrid controller, the controller 182advantageously can have a lower perceived inertia while in use.

In the illustrated embodiment, the controller 182 is configured to allowmanipulation of two medical instruments, and includes two handles 184.Each of the handles 184 is connected to a gimbal 186. Each gimbal 186 isconnected to a positioning platform 188.

As shown in FIG. 19, each positioning platform 188 includes a SCARA arm(selective compliance assembly robot arm) 198 coupled to a column 194 bya prismatic joint 196. The prismatic joints 196 are configured totranslate along the column 194 (e.g., along rails 197) to allow each ofthe handles 184 to be translated in the z-direction, providing a firstdegree of freedom. The SCARA arm 198 is configured to allow motion ofthe handle 184 in an x-y plane, providing two additional degrees offreedom.

In some embodiments, one or more load cells are positioned in thecontroller. For example, in some embodiments, a load cell (not shown) ispositioned in the body of each of the gimbals 186. By providing a loadcell, portions of the controller 182 are capable of operating underadmittance control, thereby advantageously reducing the perceivedinertia of the controller while in use. In some embodiments, thepositioning platform 188 is configured for admittance control, while thegimbal 186 is configured for impedance control. In other embodiments,the gimbal 186 is configured for admittance control, while thepositioning platform 188 is configured for impedance control.Accordingly, for some embodiments, the translational or positionaldegrees of freedom of the positioning platform 188 can rely onadmittance control, while the rotational degrees of freedom of thegimbal 186 rely on impedance control.

F. Navigation and Control.

Traditional endoscopy may involve the use of fluoroscopy (e.g., as maybe delivered through a C-arm) and other forms of radiation-based imagingmodalities to provide endoluminal guidance to an operator physician. Incontrast, the robotic systems contemplated by this disclosure canprovide for non-radiation-based navigational and localization means toreduce physician exposure to radiation and reduce the amount ofequipment within the operating room. As used herein, the term“localization” may refer to determining and/or monitoring the positionof objects in a reference coordinate system. Technologies such aspreoperative mapping, computer vision, real-time EM tracking, and robotcommand data may be used individually or in combination to achieve aradiation-free operating environment. In other cases, whereradiation-based imaging modalities are still used, the preoperativemapping, computer vision, real-time EM tracking, and robot command datamay be used individually or in combination to improve upon theinformation obtained solely through radiation-based imaging modalities.

FIG. 20 is a block diagram illustrating a localization system 90 thatestimates a location of one or more elements of the robotic system, suchas the location of the instrument, in accordance to an exampleembodiment. The localization system 90 may be a set of one or morecomputer devices configured to execute one or more instructions. Thecomputer devices may be embodied by a processor (or processors) andcomputer-readable memory in one or more components discussed above. Byway of example and not limitation, the computer devices may be in thetower 30 shown in FIG. 1, the cart 11 shown in FIGS. 1-4, the beds shownin FIGS. 5-14, etc.

As shown in FIG. 20, the localization system 90 may include alocalization module 95 that processes input data 91-94 to generatelocation data 96 for the distal tip of a medical instrument. Thelocation data 96 may be data or logic that represents a location and/ororientation of the distal end of the instrument relative to a frame ofreference. The frame of reference can be a frame of reference relativeto the anatomy of the patient or to a known object, such as an EM fieldgenerator (see discussion below for the EM field generator).

The various input data 91-94 are now described in greater detail.Preoperative mapping may be accomplished through the use of thecollection of low dose CT scans. Preoperative CT scans are reconstructedinto three-dimensional images, which are visualized, e.g. as “slices” ofa cutaway view of the patient's internal anatomy. When analyzed in theaggregate, image-based models for anatomical cavities, spaces andstructures of the patient's anatomy, such as a patient lung network, maybe generated. Techniques such as center-line geometry may be determinedand approximated from the CT images to develop a three-dimensionalvolume of the patient's anatomy, referred to as model data 91 (alsoreferred to as “preoperative model data” when generated using onlypreoperative CT scans). The use of center-line geometry is discussed inU.S. patent application Ser. No. 14/523,760, the contents of which areherein incorporated in its entirety. Network topological models may alsobe derived from the CT-images, and are particularly appropriate forbronchoscopy.

In some embodiments, the instrument may be equipped with a camera toprovide vision data (or image data) 92. The localization module 95 mayprocess the vision data 92 to enable one or more vision-based (orimage-based) location tracking modules or features. For example, thepreoperative model data 91 may be used in conjunction with the visiondata 92 to enable computer vision-based tracking of the medicalinstrument (e.g., an endoscope or an instrument advance through aworking channel of the endoscope). For example, using the preoperativemodel data 91, the robotic system may generate a library of expectedendoscopic images from the model based on the expected path of travel ofthe endoscope, each image linked to a location within the model.Intraoperatively, this library may be referenced by the robotic systemin order to compare real-time images captured at the camera (e.g., acamera at a distal end of the endoscope) to those in the image libraryto assist localization.

Other computer vision-based tracking techniques use feature tracking todetermine motion of the camera, and thus the endoscope. Some features ofthe localization module 95 may identify circular geometries in thepreoperative model data 91 that correspond to anatomical lumens andtrack the change of those geometries to determine which anatomical lumenwas selected, as well as the relative rotational and/or translationalmotion of the camera. Use of a topological map may further enhancevision-based algorithms or techniques.

Optical flow, another computer vision-based technique, may analyze thedisplacement and translation of image pixels in a video sequence in thevision data 92 to infer camera movement. Examples of optical flowtechniques may include motion detection, object segmentationcalculations, luminance, motion compensated encoding, stereo disparitymeasurement, etc. Through the comparison of multiple frames overmultiple iterations, movement and location of the camera (and thus theendoscope) may be determined.

The localization module 95 may use real-time EM tracking to generate areal-time location of the endoscope in a global coordinate system thatmay be registered to the patient's anatomy, represented by thepreoperative model. In EM tracking, an EM sensor (or tracker) comprisingone or more sensor coils embedded in one or more locations andorientations in a medical instrument (e.g., an endoscopic tool) measuresthe variation in the EM field created by one or more static EM fieldgenerators positioned at a known location. The location informationdetected by the EM sensors is stored as EM data 93. The EM fieldgenerator (or transmitter), may be placed close to the patient to createa low intensity magnetic field that the embedded sensor may detect. Themagnetic field induces small currents in the sensor coils of the EMsensor, which may be analyzed to determine the distance and anglebetween the EM sensor and the EM field generator. These distances andorientations may be intraoperatively “registered” to the patient anatomy(e.g., the preoperative model) in order to determine the geometrictransformation that aligns a single location in the coordinate systemwith a position in the preoperative model of the patient's anatomy. Onceregistered, an embedded EM tracker in one or more positions of themedical instrument (e.g., the distal tip of an endoscope) may providereal-time indications of the progression of the medical instrumentthrough the patient's anatomy.

Robotic command and kinematics data 94 may also be used by thelocalization module 95 to provide localization data 96 for the roboticsystem. Device pitch and yaw resulting from articulation commands may bedetermined during preoperative calibration. Intraoperatively, thesecalibration measurements may be used in combination with known insertiondepth information to estimate the position of the instrument.Alternatively, these calculations may be analyzed in combination withEM, vision, and/or topological modeling to estimate the position of themedical instrument within the network.

As FIG. 20 shows, a number of other input data can be used by thelocalization module 95. For example, although not shown in FIG. 20, aninstrument utilizing shape-sensing fiber can provide shape data that thelocalization module 95 can use to determine the location and shape ofthe instrument.

The localization module 95 may use the input data 91-94 incombination(s). In some cases, such a combination may use aprobabilistic approach where the localization module 95 assigns aconfidence weight to the location determined from each of the input data91-94. Thus, where the EM data may not be reliable (as may be the casewhere there is EM interference) the confidence of the locationdetermined by the EM data 93 can be decrease and the localization module95 may rely more heavily on the vision data 92 and/or the roboticcommand and kinematics data 94.

As discussed above, the robotic systems discussed herein may be designedto incorporate a combination of one or more of the technologies above.The robotic system's computer-based control system, based in the tower,bed and/or cart, may store computer program instructions, for example,within a non-transitory computer-readable storage medium such as apersistent magnetic storage drive, solid state drive, or the like, that,upon execution, cause the system to receive and analyze sensor data anduser commands, generate control signals throughout the system, anddisplay the navigational and localization data, such as the position ofthe instrument within the global coordinate system, anatomical map, etc.

2. Medical Instruments Including Wrists with Hybrid Redirect Surfaces

The robotic medical systems described above, as well as other roboticmedical systems and/or non-robotic medical systems, can use medicalinstruments that include wrists with hybrid redirect surfaces asdescribed in this section. As described above, a medical instrument caninclude an end effector positioned at the distal end of an elongatedshaft. The end effector can be connected to the distal end of theelongated shaft by a wrist. The wrist can be articulable so as to allowfor control of the end effector. As noted above, the medical instrumentcan include one or more pull wires extending through the wrist to theend effector. The one or more pull wires can be actuated (e.g., pulledor tensioned) to articulate the wrist and the end effector. As the oneor more pull wires extend through the wrist, they can be engaged withone or more pulleys within the wrist.

FIG. 21 is a side view of an embodiment of a medical instrument 200. Themedical instrument 200 can be similar to the medical instrumentsdescribed above, for example, with reference to FIGS. 16-18. Asillustrated, the medical instrument 200 includes an elongated shaft 202and a handle 208. The elongated shaft 202 extends between a distal end204 and a proximal end 206. An end effector 212, which in theillustrated embodiment is configured as a grasper, can be positioned atthe distal end 204 of the elongated shaft 202. As illustrated, the endeffector 212 can be connected to the distal end 204 of the elongatedshaft 202 by a wrist 210. The wrist 210 can be configured to allow oneor more degrees of freedom for the instrument 200. For example, thewrist 210 can be a two degree-of-freedom wrist. As an example, a twodegree-of-freedom wrist can allow the end effector 212 to pivot orrotate around a pitch axis and a yaw axis.

In the illustrated embodiment of FIG. 21, the instrument 200 includesthe handle 208. The handle 208 can be configured to connect to aninstrument drive mechanism, for example, as shown in FIGS. 16 and 17,described above. As previously mentioned, the instrument 200 may includeone or more tendons, cables, or pull wires that extend along (e.g.,through or on) the elongated shaft 202 between the end effector 212 andthe handle 208. The handle 208 may include one or more drive inputsconfigured to engage one or more drive outputs on the instrument drivemechanism (see FIGS. 16 and 17) to allow the instrument drive mechanismto actuate (e.g., tension or pull) the pull wires. Actuating the pullwires can cause motion of wrist 210 and/or the end effector 212 to allowfor remote manipulation and control of the end effector 212. Forexample, in some embodiments, actuation of the pull wires can beconfigured to cause jaws of the end effector 212 to open and closeand/or to allow the end effector 212 to rotate about pitch and/or yawaxes. As mentioned above, the instrument drive mechanism can bepositioned on a robotic arm. In some embodiments, the robotic arm can becontrolled to position, roll, advance, and/or retract the instrument200.

As shown in FIG. 21, in some embodiments, the elongated shaft 202extends through the handle 208. In such an embodiment, the elongatedshaft 202 can be configured to advance or retract relative to the handle208. In some embodiments, the instrument drive mechanism is configuredto cause the elongated shaft 202 to advance or retract relative to thehandle 208. This can allow, for example, the handle 208 to remainstationary while the elongated shaft 202 and end effector 212 areadvanced into a patient during a procedure. In some embodiments, theproximal end 206 of the elongated shaft 202 is attached to the handle208 such that the elongated shaft 202 extends only between the endeffector 212 and the handle 208.

In accordance with an aspect of the present disclosure, redirectsurfaces within the wrist 210 can be configured to change a direction ofa pull wire so as to direct the pull wire between the pulleys. As willbe described more fully below with reference to FIG. 22, some wrists mayinclude only “static” redirect surfaces. As used herein, a “static”redirect surface refers to a non-moving, or stationary surface formed onor within the wrist that contacts a pull wire to redirect it. Forexample, a static redirect surface can be a static, stationary, ornon-moving wall or channel formed on or in a clevis of the wrist alongwhich a pull wire slides as it is redirected.

In some embodiments, the medical instruments including wrists withhybrid redirect surfaces described in this section can (e.g., as shownin FIGS. 23A-23E) include at least one static redirect surface and atleast one “dynamic” redirect surface. As used herein, a “dynamic”redirect surface refers to a moving surface of the wrist that contacts apull wire to redirect it. For example, a dynamic redirect surface can bea surface of a rotating pulley of the wrist that redirects a pull wire.Examples of static and redirect surfaces will be provided below to morefully illustrate these concepts.

An alternative embodiment of a medical instrument including a wrist withhybrid redirect surfaces is also described below with reference to FIGS.27A-35. This alternative embodiment can include a wrist that redirectsat least one pull wire segment through a distal clevis of the wristusing a static redirect surface, while at least one other pull wiresegment extends through the distal clevis without contacting anyredirect surface between proximal and distal pulleys of the distalclevis.

Thus, as used in this application, the term “wrist with hybrid redirectsurfaces” can refer (1) to a wrist that is configured to use both staticand dynamic redirect surfaces (e.g., as shown in FIGS. 23A-23E), or (2)to a wrist that is configured such that certain pull wire segments areredirected using static or dynamic redirect surfaces, while otherredirect pull wire segments need not be redirected by any surface(static or dynamic) at all (e.g., as shown in FIGS. 27A-35).

In some instances, there can be both advantages and disadvantagesassociated with both static redirect surfaces and dynamic redirectsurfaces. For example, static redirect surfaces may be considered moremechanically simple as they may comprise a stationary or static surface.However, static redirect surfaces may cause more wear on pull wires.Because a static redirect surface remains stationary as it redirects apull wire, the pull wire may slide across the static redirect surface.Friction between the pull wire and the static redirect surface can causewear that can shorten the life span of the pull wire. Dynamic redirectsurfaces may reduce or eliminate the wear problems that can beassociated with static redirect surfaces. This can be because thedynamic redirect surface rotates or otherwise moves along with themovement of the pull wire, reducing the friction therebetween. This canincrease the lifespan of the pull wire. In some instances, however,dynamic redirect surfaces may be considered more mechanically complex.For example, dynamic redirect surfaces may require additional components(compared with static redirect surfaces). Further, it may be difficultto provide the additional components of a dynamic redirect surface in asmall or compact form factor as is often desirable for medicalinstruments associated with laparoscopic surgery, for example.

Some of the medical instruments including wrists with hybrid redirectsurfaces described in this section can include one or more staticredirect surfaces and one or more dynamic redirect surfaces in a mannerthat can increase the advantages associated with each while minimizingthe disadvantages. For example, in some embodiments, dynamic redirectsurfaces are implemented to redirect pull wire segments associated witha close motion (e.g., a clamping motion) of the end effector, whilestatic redirect surfaces are implemented to redirect pull wire segmentsassociated with an open motion (e.g., an unclamping motion) of the endeffector. Because it often takes more force, tension, or load to closethe end effector (or more force is generally applied in the closingdirection), the pull wire segments associated with the close motion ofthe end effector can experience more force and be exposed to more wear.By using dynamic redirect surfaces to redirect these pull wire segments,wear on the pull wires can be reduced, improving the lifespan of thepull wire. Opening the end effector can take less force, and thus thepull wire segments associated with the open motion of the end effectorcan experience less force and less wear. Thus, it can be advantageous touse static redirect for these pull wire segments because use of thesestatic redirect surfaces can be less mechanically complex.

Further, some of the medical instruments including wrists with hybridredirect surfaces described in this section can include novel structuralarchitecture that can allow for packaging of both static and dynamicredirect surfaces in a minimal form factor that is suitable for alaparoscopic or endoscopic medical instrument and that may provide oneor more additional advantages as described further below. These featuresand advantages of the medical instruments including wrists with hybridredirect surfaces will now be described in greater detail with referenceto FIGS. 21-26B.

As an aid to understanding medical instruments with wrists includinghybrid redirect surfaces (as shown, for example, in FIGS. 23A-23E, andas another example, in FIGS. 27A-35), a medical instrument with a wristincluding only static redirect surfaces will first be described withreference to FIG. 22. FIG. 22 shows a perspective view of a distal endof a medical instrument 300 that includes a wrist with only staticredirect surfaces.

As illustrated, a wrist 310 is positioned at the distal end 304 of theelongated shaft 302 of the medical instrument 300. The wrist 310includes a proximal clevis 322 and a distal clevis 324. In theillustrated embodiment, the distal clevis 324 is illustrated astransparent so as to visualize features formed within the distal clevis324. The proximal clevis 322 is connected to the distal end 304 of theelongated shaft 302. The distal clevis 324 is pivotally connected to theproximal clevis 322. For example, a proximal axle 366 can extend throughand connect the distal clevis 324 to the proximal clevis 322 such thatthe distal clevis 324 can rotate relative to the proximal clevis 322about a longitudinal axis of the proximal axle 366. This may allow thewrist 310 to move or articulate in a first degree of freedom. The firstdegree of freedom may be pitch.

As shown in FIG. 22, a plurality of pulleys 340 can also be mounted onthe proximal axle 366 at the joint between the proximal clevis 322 andthe distal clevis 324. In the illustrated embodiment, four proximalpulleys 340 are included. As will be described in more detail below, aplurality of pull wires (not shown) can be engaged with the proximalpulleys 340 and actuated to control the pitch of the medical instrument300.

An end effector 312 is connected to the distal clevis 324. In theillustrated embodiment, the end effector 312 comprises a gripper havinga first jaw member 356 and a second jaw member 358. Other types of endeffectors can also be used, such as graspers, cutters, scissors, etc. Inthe illustrated embodiment, each of the jaw members 356, 358 isconnected to one of two distal pulleys 350 connected to the distalclevis 324. An example jaw member is shown alone in FIG. 24, which isdescribed below. As illustrated, a distal axle 367 can extend throughthe distal clevis 324, and the distal pulleys 350 can be rotatablymounted on the distal axle 367. The distal pulleys 350 can thus rotaterelative to the distal clevis 324 to allow the end effector 312 torotated in a second degree of freedom. The second degree of freedom canbe yaw. Additionally, if the distal pulleys 350 are rotated in oppositedirections, a third degree of freedom can be provided. The third degreeof freedom can be opening and closing the end effector 312. Theplurality of pull wires (not shown) can be engaged with the distalpulleys 350 and actuated to control the pitch of the medical instrument300 and to open and close the end effector 312.

As illustrated in FIG. 22, the proximal axle 366 and the distal axle 367can be oriented along axes that extend in different directions. In theillustrated embodiment, the proximal axle 366 extends along the pitchaxis and the distal axle 367 extends along the yaw axis. The pitch andyaw axes can be orthogonal to each other. Thus, the proximal pulleys 340and the distal pulleys 350 rotate in different planes, which, in theillustrated embodiment, are orthogonal to each other. As the pluralityof pull wires are engaged with both the proximal pulleys 340 and thedistal pulleys 350, the plurality of pull wires need to be redirectedbetween the proximal pulleys 340 and the distal pulleys 350. Forexample, the plurality of pull wires need to be redirected from theplane of proximal pulleys 340 to the plane of the distal pulleys 350. Tofacilitate redirection of the pull wires, the distal clevis 324 includesa plurality of static redirect surfaces 326 that are configured toredirect the plurality of pull wires. As shown, the static redirectsurfaces 326 comprise angled or curved faces formed in the distal clevis324 for redirecting the plurality of pull wires. As the various pullwire segments of the plurality of pull wires are actuated, the pull wiresegments slide across the static redirect surfaces 326 as they areredirected.

The static redirect surfaces 326 can be provided to change a course ofdirection for one or more pull wire segments of the plurality of pullwires. In the medical instrument 300 of FIG. 22, the wrist 310 comprisesa distal clevis 324 having only static redirect surfaces 326, in theform of one or more angled, curved or sloped surfaces. While such staticredirect surfaces 326 can successfully redirect the pull wires, thesliding of the pull wire segments against the static redirect surfaces326 can cause abrasion to the outside of the pull wires due to increasedfriction, thereby reducing pull wire life. In addition, the spaceavailable for static redirect surfaces 326 between the proximal pulleys340 and the distal pulleys 350 can be limited.

The medical instrument 300 shown in FIG. 22 can be considered an N+1medical instrument because it achieves three degrees of freedom (pitch,yaw, and instrument actuation) using four pull wire segments.

In contrast with the medical instrument 300 of FIG. 22, FIGS. 23A-23Eillustrate a medical instrument 400 with a wrist that includes hybridredirect surfaces. That is, in this example, the wrist of FIGS. 23A-23Eincludes both static redirect surfaces and dynamic redirect surfaces.Use of hybrid redirect surfaces within the wrist can alleviate wear onthe pull wires. While FIGS. 23A-23E illustrate an example configured asa grasper instrument, one skilled in the art will appreciate that theuse of hybrid redirect surfaces is not limited to instruments simply forgrasping, but can be applicable to many other instruments as well (e.g.,cauterization instruments, cutting instruments, suction and irrigationinstruments, etc.).

As will be described below, the medical instrument 400 of FIGS. 23A-23Eincludes both static and dynamic redirect surfaces to realize both thepackaging benefits of static redirect surfaces and the performance andlife improvements of dynamic redirect surfaces. As mentioned above,during operation, the pull wire segments associated with closing the endeffector may have significantly more load on them the pull wire segmentsassociated with opening the end effector. Thus, most of the benefits ofdynamic redirect surfaces can be realized by having the dynamic redirectsurfaces engaged with the pull segments associated with closing the endeffector. At the same time, pull wire segments that experience less loadand tension can be redirected using static redirect surfaces.

The structure of the medical instrument 400 will be described withreference to FIGS. 23A-23E. FIG. 23A is a perspective view of themedical instrument 400. FIG. 23B is another perspective view of themedical instrument 400, shown with a distal clevis 424 illustrated astransparent so as to visualize certain internal features thereof. FIG.23C is a is a first side view of the medical instrument 400. FIG. 23D isa second side view of the medical instrument 400. FIG. 23E is a top viewof a proximal clevis 422 of the medical instrument 400.

As shown in FIG. 23A, in the illustrated embodiment, the medicalinstrument 400 includes an elongated shaft 402 extending to a distal end404. Only the distal end 404 of the elongated shaft 402 is visible inFIG. 23A, but the elongated shaft 402 may be similar to the elongatedshaft 202 of the medical instrument 200 described above. A wrist 410 ispositioned at the distal end 404 of the elongated shaft 402. The wrist410 is also connected to an end effector 412, which as noted above is agrasper in the illustrated embodiment. As will be described in moredetail below, the wrist 410 can be configured to allow articulation intwo degrees of freedom. In the example described below, the two degreesof freedom are pitch and yaw. Additionally, the end effector 412 canopen and close providing an additional degree of freedom for the medicalinstrument 400. The medical instrument 400 can be considered an N+1medical instrument because it achieves three degrees of freedom (pitch,yaw, and instrument actuation) using four pull wire segments.

In the illustrated embodiment, the wrist 410 comprises a proximal clevis422 and a distal clevis 424. The proximal clevis 422 can be attached tothe distal end 404 of the elongated shaft 402. The distal clevis 424 canbe pivotally attached to the proximal clevis 422. In the illustratedembodiment, the distal clevis 424 is pivotally attached to the proximalclevis 422 by an axle 466 which extends through the distal clevis 424and the proximal clevis 422. The distal clevis 424 can rotate about anaxis of the axle 466 relative to the proximal clevis 422. Rotation ofthe distal clevis 424 about an axis of the axle 466 relative to theproximal clevis 422 can provide one of the degrees of freedom of thewrist 410. For example, this degree of freedom can be pitch. Thus, theaxle 466 can be considered a pitch axle and the axis of the axle 466 canbe considered the pitch axis of the wrist 410.

As best seen in FIG. 23C, the proximal clevis 422 can include a firstproximal clevis support leg 474 and a second proximal clevis support leg476. The axle 466 can extend through the first proximal clevis supportleg 474 and the second proximal clevis support leg 476 of the proximalclevis 422. Similarly, the distal clevis 424 can include a first distalclevis support leg 470 and a second distal clevis support leg 472. Theaxle 466 extends through the first distal clevis support leg 470 and thesecond distal clevis support leg 472 of the distal clevis 424. As willbe described below, in some embodiments, the first proximal clevissupport leg 474, the second proximal clevis support leg 476, the firstdistal clevis support leg 470, and the second distal clevis support leg472 can be spaced in a manner that can provide an advantageousarchitecture for medical instruments with wrists having hybrid redirectsurfaces.

As shown in FIGS. 23A-23D, the medical instrument 400 includes aplurality of proximal pulleys 440 and a plurality of distal pulleys 450positioned in the wrist 410. As best seen in FIGS. 23A-23C, the proximalpulleys 440 can be positioned on the axle 466 that connects the proximalclevis 422 and the distal clevis 424. As noted above, the axle 466 canbe a pitch axle, and thus, the proximal pulleys 440 may also beconsidered pitch pulleys 440. In the illustrated embodiment, theproximal pulleys 440 include a first outer proximal pulley 442, a firstinner proximal pulley 444, a second outer proximal pulley 446, and asecond inner proximal pulley 448. The first outer proximal pulley 442,the first inner proximal pulley 444, the second outer proximal pulley446, and the second inner proximal pulley 448 can each be positioned onthe axle 466 such that they can rotate about the axle 466. The proximalpulleys 440 each rotate in a pitch plane that is perpendicular to theaxis of the axle 466.

As seen in FIGS. 23A-23D, the distal pulleys 450 can be positioned on anaxle 467. The axle 467 can extend through the distal clevis 424 asshown. The axis of the axle 467 can provide a second degree of freedomfor the medical instrument 400. For example, this second degree offreedom can be yaw. Accordingly, the axle 467 can be considered a yawaxle and can provide a yaw axis for the wrist 410. In the illustratedembodiment, the distal pulleys 450 include a first distal pulley 452 anda second distal pulley 454 mounted on the axle 467. Each of the distalpulleys 450 can be configured rotate in a yaw plane that isperpendicular to the axis of axle 467.

The pitch axle 466 and the yaw axle 467 can be oriented at an angle withrespect to each other. In the illustrated example, the pitch axle 466and the yaw axle 467 are orthogonal. Accordingly, the pitch plane andthe yaw plane can also be orthogonal to each other.

The end effector 412 of the medical instrument 400 can be formed by afirst jaw member 456 and a second jaw member 458. The first jaw member456 can be connected to the first distal pulley 452 and the second jawmember 458 can be connected to the second distal pulley 454. Theorientation of the end effector 412 can be controlled by rotating thefirst distal pulley 452 and the second distal pulley 454 in the samedirection about the axle 467. For example, by rotating both of the firstdistal pulley 452 and the second distal pulley 454 in the same directionabout the axle 467 the yaw of the end effector 412 can be adjusted. Theend effector 412 can be actuated (e.g., opened or closed in the case ofthe illustrated grasper) by rotating the first distal pulley 452 and thesecond distal pulley 454 in the opposite directions about the axle 467.Actuation of the end effector 412 can be considered a third degree offreedom of the medical instrument 400.

The medical instrument 400 can include a plurality of pull wires 430that can be actuated (e.g., pulled or tensioned) to control the threedegrees of freedom of the medical instrument 400 (pitch, yaw, andactuation). As shown in FIGS. 23A-23D, the plurality of pull wires 430are engaged with the proximal pulleys 440 and the distal pulleys 450. Inthe illustrated embodiment, the plurality of pull wires 430 include afirst pull wire segment 432, a second pull wire segment 434, a thirdpull wire segment 436, and a fourth pull wire segment 438 which arerouted along various paths through the wrist 410.

For example, in the illustrated embodiment, the first pull wire segment432 engages the first outer proximal pulley 442 and the first distalpulley 452. Actuation of the first pull wire segment 432 can beassociated with closing the first jaw member 456. The second pull wiresegment 434 can be engaged with the first inner proximal pulley 444 andthe second distal pulley 454. The second pull wire segment 434 can beassociated with opening the second jaw member 458. The third pull wiresegment 436 can be engaged with the second outer proximal pulley 446 andsecond distal pulley 454. The third pull wire segment 436 can beassociated with closing the second jaw member 458. The fourth pull wiresegment 438 can be engaged with the second inner proximal pulley 448 andthe first distal pulley 452. The fourth pull wire segment 438 can beassociated with opening the first jaw member 456.

As shown in the figures, each of the first pull wire segment 432 and thefourth pull wire segment 438 can engage the first distal pulley 452, buton opposite sides. Similarly, each of the second pull wire segment 434and the third pull wire segment 436 can engage the second distal pulley454, but on opposite sides. In the illustrated embodiment, each of theproximal pulleys 440 is only engaged by one of the pull wire segments.The first pull wire segment 432 engages the first outer proximal pulley442 on the same side of the wrist 410 that the fourth pull wire segment438 engages the second inner proximal pulley 448. Similarly, the secondpull wire segment 434 engages the first inner proximal pulley 444 on thesame side of the wrist 410 that the third pull wire segment 436 engagesthe second outer, proximal pulley 446. At the proximal pulleys 440, thefirst and fourth pull wire segments 432, 438 are positioned on anopposite side of the wrist 410 than the second and third pull wiresegments 434, 436.

As best seen in FIG. 23B, which illustrates the distal clevis 424 astransparent, the plurality of pull wires 430 are redirected betweenproximal pulleys 440 and distal pulleys 450. To accomplish theredirection, the wrist 410 of the instrument 400 includes hybridredirect surfaces. Specifically, in the illustrated embodiment, thewrist 410 includes a pair of static redirect surfaces and a pair ofdynamic redirect surfaces positioned between proximal pulleys 440 anddistal pulleys 450. As shown in FIG. 23B, the pair of static redirectsurfaces include a first static redirect surface 426 and a second staticredirect surface 433. The first static redirect surface 426 and thesecond static redirect surface 433 can each be an angled or curvedsurface formed in or on the distal clevis 424. An example, is visible inFIG. 23C, which shows the static redirect surface 426. The pair ofdynamic redirect surfaces include a first dynamic redirect surface 428and a second dynamic redirect surface 431. Each of the first dynamicredirect surface 428 and the second dynamic redirect surface 431 cancomprise a surface of a redirect pulley, such as the first redirectpulley 429 and the second redirect pulley 435 that are illustrated inthe figures.

The plurality of pull wires 430 are redirected by the static redirectsurfaces 426, 433 and the dynamic redirect surfaces 428, 431. In theillustrated embodiment, the first pull wire segment 432 engages thefirst dynamic redirect surface 428. The second pull wire segment 434engages the first static redirect surface 426. The third pull wiresegment 436 engages the second dynamic redirect surface 431. The fourthpull wire segment 438 engages the second static redirect surface 433.

Thus, in this example, the first and third pull wire segments 432, 436,which are associated with closing the end effector 412 are redirectedusing the dynamic redirect surfaces 428, 431 of the redirect pulleys429, 435, respectively. The second and fourth pull wire segments 434,438, which are associated with opening the end effector 412 areredirected using the static redirect surfaces 426, 433, respectively.

The medical instrument 400 also includes shaft redirect pulleys 480positioned in the proximal clevis 422 and/or within the elongated shaft402. The shaft redirect pulleys 480 are best seen in FIG. 23E which is atop down view of the proximal clevis 422. As shown, the shaft redirectpulleys 480 include a first outer shaft redirect pulley 482, a firstinner shaft redirect pulley 484, a second outer shaft redirect pulley486, and second inner shaft redirect pulley 488. In the illustratedembodiment, the shaft redirect pulleys 480 are in a staggered position.That is, as shown in FIG. 23E, the first outer shaft redirect pulley 482is positioned on first axis 483 and the first inner shaft redirectpulley 484 is positioned on second axis 485. The first and second axes483, 485 are not coaxial (in the illustrated embodiment). The secondinner shaft redirect pulley 488 is positioned on a third axis 489. Inthe illustrated embodiment the third axis 489 is coaxial with secondaxis 485. The second outer shaft redirect pulley 486 is positioned onfourth axis 487. In the illustrated embodiment, the fourth axis 487 isnot coaxial with the first, second, or third axes 483, 485, 489. Theproximal clevis 422 also comprises a first proximal clevis support wall492 and a second proximal clevis support wall 494. The a first proximalclevis support wall 492 is positioned between the first inner and outershaft redirect pulleys 482, 484. The second proximal clevis support wall494 is positioned between the second inner and outer shaft redirectpulleys 486, 484. The first proximal clevis support leg 474 and thesecond proximal clevis support leg 476 are also shown in FIG. 23E.

The structure of the medical instrument 400 (which includes hybridredirect surfaces) can provide several notable features and advantagesover other types of medical instruments, such as medical instrumentsthat only include static redirect surfaces (e.g., FIG. 22). For example,with respect to the illustrated embodiment of the medical instrument 400(shown as a grasper instrument), during operation, the pull wiresegments that are associated with closing the end effector 412 (thefirst and third pull wire segments 432, 436) can have greater load thanpull wire segments that are used for opening the end effector 412 (thesecond and fourth pull wire segments 434, 438). As such, it can beparticularly beneficial to have pull wire segments for closing the endeffector 412 run along the dynamic redirect surfaces 428, 431 so as toreduce the risk of pull wire wear, while having pull wires segments foropening the end effector 412 run along the static redirect surfaces 426,433, as illustrated in FIG. 23B. Because the dynamic redirect surfaces428, 431 move with the first and third pull wire segments 432, 436 (asthe redirect pulleys 429, 435 rotate) friction between the dynamicredirect surfaces 428, 431 and the pull wire segments 432, 436 can bereduced when compared to the friction experienced between pull wiresegments and static redirect surface. As noted previously, this canextend the lifespan of the pull wires.

The structure of the medical instrument 400 can include several featuresthat enable or facilitate the use of hybrid redirect surfaces within thedistal clevis 424. First, the distal clevis support legs 470, 472 of thedistal clevis 424 can be positioned between the inner and outer proximalpulleys. For example, as shown in FIG. 23D, the first distal clevissupport leg 470 is positioned between the first outer proximal pulley442 and the first inner proximal pulley 444. Similarly, the seconddistal clevis support leg 472 is positioned between the second outerproximal pulley 446 and the second inner, proximal pulley 448. Thisarrangement or architecture provides for a distance of separationbetween the stationary redirect surfaces 426, 433 and the dynamicredirect surface 428, 431 (e.g., the redirect pulleys 429, 435). Thisdistance can provide clearance and enough room to mount the redirectpulleys 429, 435 and for adjacent pull wire segments to pass withoutinterference. This is best seen in FIG. 23D. Because the first distalclevis support leg 470 is positioned between the first outer, proximalpulley 442 and the first inner, proximal pulley 444 the third pull wiresegment 446 has additional room to cross behind the first redirectpulley 429. Additionally, this configuration can allow the axle of theredirect pulley 429 to be on the outside of the distal clevis supportleg 470, so that the distal clevis support leg 470 does not need to becut through to accommodate the axle.

Second, the dynamic redirect pulleys 429, 432 can be sized such thatthey can reach across to the far distal pulley 450. This can enable alarger redirect pulley 429, 432 to be fit within the distal clevis 424,which can improve the lifetime of the pull wire segment that travelsthere over. Larger dynamic redirect surfaces (e.g., redirect pulleys)can often lead to larger life performance. As such, it is of benefit toinclude as large of a redirect pulley as possible within the limitedspace between the distal and proximal pulleys. This is shown in FIG.23D. The redirect cable 439 is sufficiently large such that pull wiresegment 432 crosses from a first lateral side 462 of the to a secondlateral side 464 (across plane 460) to the first distal pulley 452,which is located on the opposite side from where the pull wire segment432 engages the first outer proximal pulley 431. In some embodiments, toaccommodate the larger dynamic redirect pulley 429, the stationaryredirect surface 426 is designed to cross behind the pulley 429 withoutintersection (see FIG. 23C), which is enabled by the extra room providedby the distal clevis support leg (discussed above).

Third, in the illustrated embodiment, the outer shaft redirect pulleys482, 486 in the proximal clevis 422 do not share a common axis with theinner shaft redirect pulleys 484, 488 in the proximal clevis 422. Notethat the shaft redirect pulleys 480 (see FIG. 23E) all provide dynamicredirect surfaces. This can be possible because there may be greaterroom within the proximal clevis 422 to accommodate the shaft redirectpulleys 480. As noted above, larger dynamic redirect surfaces (e.g.,redirect pulleys) can often lead to longer life performance. In someinstances, staggering the shaft redirect pulleys 480 can allow forlarger pulleys to be used. Further, the addition of the distal clevissupport legs 470, 472 between the inner and outer proximal pulleys 440can push out the location of the corresponding shaft redirect pulleys480 that are located in the shaft 402 of the medical instrument 400. Asthe outer shaft redirect pulleys 482, 486 are pushed out, there is lessspace to fit the multiple (e.g., four) shaft redirect pulleys 480 alonga common axis. While it is possible to reduce the size of one or moreproximal redirect pulleys 480, this may reduce the life and performancebenefits. Accordingly, in the illustrated embodiment, the proximalredirect pulleys 480 are sized such that cables are maintained withinthe inner diameter of the instrument shaft 402, while the edge of theouter shaft redirect pulleys 482, 486 are just inside the outer diameterof the instrument shaft 402.

These three features noted in the preceding paragraphs can provide anadvantageous wrist structure using hybrid redirect surfaces. In someembodiments, not all three features need be included.

FIG. 24 illustrates an embodiment of the first distal pulley 452 andattached jaw member 456 as well as the first pull wire segment 432 andthe fourth pull wire segment 438. FIG. 24 is also representative of thesecond distal pulley 454 with associated second pull wire segment 434and third pull wire segment 436. As noted above, the first pull wiresegment 432 is associated with opening the jaw member 456 and the fourthpull wire segment 438 is associated with closing the jaw member 456. Insome embodiments, the two pull wire segments 432, 438 can be part of thesame pull wire, or each part of different pull wires that share a crimpat the jaw member 456.

FIGS. 25A and 25B illustrate an alternative embodiment of a distalclevis 522 that includes hybrid redirect surfaces. In this embodiment,dynamic redirect surfaces 529 (configured as pulleys) are configured toredirect pull wires 530 along a path that crosses from a far pitchpulley 540 to the opposite side of the yaw pulley 550. In thisembodiment, the proximal pitch pulleys 540 can be all centered andaligned, which can allow them to be larger in size as they are allcentered.

FIGS. 26A and 26B provide views of another embodiment of a distal clevis622. In this embodiment, the stationary redirect surfaces have beenreplaced with dynamic redirect surfaces. Accordingly, the distal clevis622 includes four redirect pulleys 629. In such a case, the instrumentwould not be considered to have a hybrid redirect surface because itonly includes one type of redirect surface (dynamic).

FIGS. 27A-35 relate to an alternative embodiment of a medical instrument700 that includes a wrist having hybrid redirect surfaces. In contrastwith the previously described medical instrument 400 of FIGS. 23A-23E,which included both static redirect surfaces 426, 433 and dynamicredirect surfaces 428, 431, the medical instrument 700 includes a hybridclevis design wherein at least one pull wire segment (e.g., a jaw opencable segment) is designed to pass over a redirect surface (such as astatic redirect surface or a dynamic redirect surface), while anotherpull wire cable segment (e.g., a jaw close cable segment) is designed tohave no redirect surface at all. As will be described in more detailbelow, with this design, jaw close pull wire segments can be givenpreferential treatment over the jaw open pull wire segments. In someembodiments of the medical instrument 700, while the jaw open pull wiresegments extend over redirect surfaces, the jaw close pull wire segmentsextend nearly vertically or straight (with respect to a longitudinalaxis of the instrument) between distal pulleys of a distal clevis (e.g.,pitch pulleys) and the proximal pulleys of the distal clevis (e.g., yawpulleys), as shown and described below.

In some embodiments, the medical instrument 700 can be an energydelivering instrument (e.g., a bipolar instrument or a monopolarinstrument). As such, in addition to the pull wire segments, theinstrument can include electrical cable segments for energizing theinstrument. As described below, the medical instrument 700 canadvantageously accommodate the electrical cable segments, whilemaintaining a compact form factor suitable for laparoscopic surgery.

FIGS. 27A and 27B are perspective views of the medical instrument 700.In FIG. 27B, a distal clevis 724 of the medical instrument 700 isillustrated as transparent so as to visualize certain internal featuresthereof. The medical instrument 700 can be positioned at the end (forexample, at the distal end) of the an elongated shaft as described above(see, for example, FIG. 21). As illustrated in FIGS. 27A and 27B, themedical instrument 700 can comprise a wrist 710. The wrist 710 can bepositioned at the distal end of the elongated shaft.

The wrist 710 can also be connected to an end effector 712, which in theillustrated embodiment, is configured as a grasper, although other typesof end effectors are possible. As will be described in more detailbelow, the wrist 710 can be configured to allow articulation in twodegrees of freedom. In the illustrated example, the two degrees offreedom are pitch and yaw. Additionally, the end effector 712 can openand close providing an additional degree of freedom for the medicalinstrument 700. The medical instrument 700 can be considered an N+1medical instrument because it achieves three degrees of freedom (pitch,yaw, and instrument actuation) using four pull wire segments.

In the illustrated embodiment, the wrist 710 comprises a proximal clevis722 and a distal clevis 724. The proximal clevis 722 can be configuredto attach to the distal end of the elongated shaft. The distal clevis724 can be pivotally attached to the proximal clevis 722. In theillustrated embodiment, the distal clevis 724 is pivotally attached tothe proximal clevis 722 by an axle 766 which extends through the distalclevis 724 and the proximal clevis 722. The distal clevis 724 can rotateabout an axis of the axle 766 relative to the proximal clevis 722.Rotation of the distal clevis 724 about an axis of the axle 766 relativeto the proximal clevis 722 can provide one of the degrees of freedom ofthe wrist 710. For example, this degree of freedom can be pitch. Thus,the axle 766 can be considered a pitch axle and the axis of the axle 766can be considered the pitch axis of the wrist 710.

As shown in FIGS. 27A and 27B (and also in FIGS. 28 and 31, describedbelow), the proximal clevis 722 can include a first proximal clevissupport leg 774 and a second proximal clevis support leg 776. The axle766 can extend through the first proximal clevis support leg 774 and thesecond proximal clevis support leg 776 of the proximal clevis 722.Similarly, the distal clevis 724 can include a first distal clevissupport leg 770 and a second distal clevis support leg 772. The axle 766extends through the first distal clevis support leg 770 and the seconddistal clevis support leg 772 of the distal clevis 724.

The medical instrument 700 can also include a plurality of proximalpulleys 740 and a plurality of distal pulleys 750 positioned in thewrist 710. The proximal pulleys 740 can be positioned on the axle 766that connects the proximal clevis 722 and the distal clevis 724. Asnoted above, the axle 766 can be a pitch axle, and thus, the proximalpulleys 740 may also be considered pitch pulleys 740. In the illustratedembodiment, the proximal pulleys 740 include a first outer proximalpulley 742, a first inner proximal pulley 744, a second outer proximalpulley 746, and a second inner proximal pulley 748. The first outerproximal pulley 742, the first inner proximal pulley 744, the secondouter proximal pulley 746, and the second inner proximal pulley 748 areeach positioned on the axle 766 such that they can rotate about the axle766. The proximal pulleys 740 each rotate in a pitch plane that isperpendicular to the axis of the axle 766.

The arrangement of the first outer proximal pulley 742, the first innerproximal pulley 744, the second outer proximal pulley 746, and thesecond inner proximal pulley 748 is also shown in FIG. 28, which is across-sectional view taken along the axis of the axle 766. As shown inFIG. 28, the first outer proximal pulley 742, the first inner proximalpulley 744, the second outer proximal pulley 746, and the second innerproximal pulley 748 are arranged along the axle 766. Further, in theillustrated embodiment, the first outer proximal pulley 742, the firstinner proximal pulley 744, the second outer proximal pulley 746, and thesecond inner proximal pulley 748 are all positioned between the firstproximal clevis support leg 774 and the second proximal clevis supportleg 776. The first distal clevis support leg 770 and the second distalclevis support leg 772 can be positioned between the outer and innerproximal pulleys. For example, as illustrated, the first distal clevissupport leg 770 is positioned between the first outer proximal pulley742 and the first inner proximal pulley 744, and the second distalclevis support leg 772 is positioned between the second outer proximalpulley 746 and the second inner proximal pulley 748.

As illustrated in FIGS. 27A and 27B, the distal pulleys 450 arepositioned on an axle 767. The axle 767 can extend through the distalclevis 724 as shown. The axis of the axle 767 can provide a seconddegree of freedom for the medical instrument 700. For example, thissecond degree of freedom can be yaw. Accordingly, the axle 767 can beconsidered a yaw axle and can provide a yaw axis for the wrist 710. Inthe illustrated embodiment, the distal pulleys 750 include a firstdistal pulley 752 and a second distal pulley 754 mounted on the axle767. Each of the distal pulleys 750 can be configured rotate in a yawplane that is perpendicular to the axis of axle 767. The first andsecond distal pulleys 752, 754 are also shown in the top view of themedical instrument 700 of FIG. 29. As will be described in more detailbelow, the first and second distal pulleys 752, 754 can each beconfigured to engage with pull wire segments for rotating the first andsecond distal pulleys 752, 754 and, in the case of an energy deliveryinstrument, for example, as illustrated, an electrical cable segment790, 792. The pitch axle 766 and the yaw axle 767 can be oriented at anangle with respect to each other. In the illustrated example, the pitchaxle 766 and the yaw axle 767 are orthogonal. Accordingly, in someembodiments, the pitch plane and the yaw plane can also be orthogonal toeach other.

In the illustrated embodiment, the end effector 712 of the medicalinstrument 700 is formed by a first jaw member 756 and a second jawmember 758. The first jaw member 756 can be connected to the firstdistal pulley 752 and the second jaw member 758 can be connected to thesecond distal pulley 754. The orientation of the end effector 712 can becontrolled by rotating the first distal pulley 752 and the second distalpulley 754 in the same direction about the axle 767. For example, byrotating both of the first distal pulley 752 and the second distalpulley 754 in the same direction about the axle 767 the yaw of the endeffector 712 can be adjusted. The end effector 712 can be actuated(e.g., opened or closed in the case of the illustrated grasper) byrotating the first distal pulley 752 and the second distal pulley 754 inthe opposite directions about the axle 767. Actuation of the endeffector 712 can be considered a third degree of freedom of the medicalinstrument 700. As described below, the first and/or second jaw members756, 758 can be energized by electrical cable segments 790, 792.

The medical instrument 700 includes a plurality of pull wires 730 thatcan be actuated (e.g., pulled or tensioned) to control the three degreesof freedom of the medical instrument 700 (e.g., pitch, yaw, andactuation). As shown in FIGS. 27A and 27B, the plurality of pull wires730 can be engaged with the proximal pulleys 740 and the distal pulleys750. In the illustrated embodiment, the plurality of pull wires 730 caninclude a first pull wire segment 732, a second pull wire segment 734, athird pull wire segment 736 (not visible in FIGS. 27A and 27B), and afourth pull wire segment 738 which are routed along various pathsthrough the wrist 710.

For example, in the illustrated embodiment, the first pull wire segment732 engages the first outer proximal pulley 742 and the first distalpulley 752. Actuation of the first pull wire segment 732 can beassociated with closing the first jaw member 756. The second pull wiresegment 734 can be engaged with the first inner proximal pulley 744 andthe second distal pulley 754. The second pull wire segment 734 can beassociated with opening the second jaw member 758. The third pull wiresegment 736 can be engaged with the second outer proximal pulley 746 andsecond distal pulley 754. The third pull wire segment 736 can beassociated with closing the second jaw member 758. The fourth pull wiresegment 738 can be engaged with the second inner proximal pulley 748 andthe first distal pulley 752. The fourth pull wire segment 438 can beassociated with opening the first jaw member 756.

As seen in the top view of FIG. 29, each of the first pull wire segment732 and the fourth pull wire segment 738 can engage the first distalpulley 752, but on opposite sides. Similarly, each of the second pullwire segment 734 and the third pull wire segment 736 can engage thesecond distal pulley 754, but on opposite sides. As best shown in thecross-sectional view of FIG. 28, each of the proximal pulleys 740 may beonly engaged by one of the pull wire segments. The first pull wiresegment 732 may engage the first outer proximal pulley 742 on the sameside of the wrist 710 that the fourth pull wire segment 738 engages thesecond inner proximal pulley 748. Similarly, the second pull wiresegment 734 may engage the first inner proximal pulley 744 on the sameside of the wrist 710 that the third pull wire segment 736 engages thesecond outer, proximal pulley 746. At the proximal pulleys 740, thefirst and fourth pull wire segments 732, 738 can be positioned on anopposite side of the wrist 710 than the second and third pull wiresegments 734, 736.

As shown in FIGS. 27A and 27B, the plurality of pull wires 730 extendalong various paths between proximal pulleys 740 and distal pulleys 750.Advantageously, some of the pull wires 730 can be provided withpreferential paths (e.g., more direct or otherwise advantageous paths)through the wrist 710. For example, in the illustrated embodiment, thefirst pull wire segment 732 and the third pull wire segment 736 areprovided with preferential cable paths when compared with the secondpull wire segment 734 and the fourth pull wire segment 738. In thisexample, the cable paths for the first pull wire segment 732 and thethird pull wire segment 736 are referred to as preferential because thefirst pull wire segment 732 and the third pull wire segment 736 extendbetween the proximal pulleys 740 and the distal pulleys 750 along cablepaths that are shorter than the cable paths for the second pull wiresegment 734 and the fourth pull wire segment 738. Additionally, in theillustrated example, the cable paths for the first pull wire segment 732and the third pull wire segment 736 are referred to as preferentialbecause the first pull wire segment 732 and the third pull wire segment736 extend between the proximal pulleys 740 and the distal pulleys 750without contacting any redirect surface (either static or dynamic).

This can be seen with respect to the first pull wire segment 732, asshown in FIGS. 27A and 27B. In this example, the first pull wire segment732 extends between the first outer proximal pulley 742 and the firstdistal pulley 752 along a preferential cable path. As shown, the firstpull wire segment 732 extends along a substantially straight cable pathbetween the first outer proximal pulley 742 and the first distal pulley752. The substantially straight cable path can be generally aligned witha longitudinal or central axis of the medical instrument 700 asdiscussed further below with reference to FIG. 35. For example, in someembodiments, an angle of the cable path of the first pull wire segment732 with respect to the longitudinal or central axis of the medicalinstrument 700 can be less than 10 degrees or less than 5 degrees.Further, as shown in FIGS. 27A and 27B, the first pull wire segment 732extends between the first outer proximal pulley 742 and the first distalpulley 752 along a preferential cable path because it is not redirectedwith any redirect surface between the first outer proximal pulley 742and the first distal pulley 752. Rather, the first pull wire segment 732can extend between the first outer proximal pulley 742 and the firstdistal pulley 752 without contacting any redirect surface. Although thethird pull wire segment 736 is not visible in FIGS. 27A and 27B, thethird pull wire segment 736 can also extend along a similar preferentialcable path.

In contrast, with the preferential cable paths of the first and thirdpull wire segments 732, 736, the second and fourth pull wire segments734, 738 are redirected as they extend through the distal clevis 724 ofthe wrist 710. For example, as shown in FIGS. 27A and 27B, the secondand fourth pull wire segments 734, 738 contact first and second redirectsurfaces 726, 731, respectively. In the illustrated embodiment, thefirst and second redirect surfaces 726, 731 are static redirect surfacesformed in the distal clevis 724. In some embodiments, however, the firstand second redirect surfaces 726, 731 can comprise dynamic redirectsurfaces. For example, the first and second redirect surfaces 726, 731can comprises surfaces of redirect pulleys.

In the illustrated embodiment, the first and second redirect surfaces726, 731 redirect (e.g., change the direction of) the second and fourthpull wire segments 734, 738 as they extend through distal clevis 724between the proximal and distal pulleys 740, 750. In the illustratedembodiment, the second pull wire segment 734 engages the first staticredirect surface 726, and the third pull wire segment 736 engages thesecond dynamic redirect surface 731.

Because the second and fourth pull wire segments 734, 738 are redirectedas they extend through distal clevis 724, the cable path lengths of thesecond and fourth pull wire segments 734, 738 can be longer than thecable path lengths of the first and third pull wire segments 732, 736.Stated another way, the cable path lengths of the first and third pullwire segments 732, 736 can be shorter than the cable path lengths of thesecond and fourth pull wire segments 734, 738 between the proximal anddistal pulleys 740, 750. The shorter cable path lengths of the first andthird pull wire segments 732, 736 can provide another reason why thecable path lengths of the first and third pull wire segments 732, 736are referred to as preferential over the cable path lengths of thesecond and fourth pull wire segments 734, 738.

As noted previously, the first and third pull wire segments 732, 736 canbe associated with a close motion (e.g., a clamping motion) of themedical instrument 700 and the second and fourth pull wire segments 734,738 can be associated with an open motion (e.g., an unclamping motion)of the medical instrument 714. During operation, the pull wire segmentsthat are associated with closing the end effector 712 (the first andthird pull wire segments 732, 736) can have greater load (e.g., greatertension or force) than pull wire segments that are used for opening theend effector 712 (the second and fourth pull wire segments 734, 738). Assuch, it can be particularly beneficial to have pull wire segments forclosing the end effector 412 run along preferred cable paths as shown inFIGS. 27A and 27B. For example, it can be advantageous that the firstand third pull wire segments 732, 736 do not (or have limited) contactthe redirect surfaces between the proximal and distal pulleys 740, 750.This can be because avoiding contact with a redirect surface can reduceor eliminate reduce the risk of pull wire wear, which can be especiallygreat for the pull wire segments associated with closing the endeffector 712 because these pull wire segments undergo greater forces. Incontrast, the pull wire segments for opening the end effector 712 runalong the redirect surfaces 726, 731 as illustrated in FIGS. 27A and27B. Running these pull wire segments along the redirect surfaces 726,731 can facilitate an advantageously compact architecture for the wrist,and because the forces and loads associated with opening the endeffector 712 are lighter, wear on these pull wire segments can beminimized. This can extend the lifespan of the pull wires 730 of themedical instrument 700.

In the illustrated embodiment of FIGS. 27A and 27B, the medicalinstrument 700 comprises an energy delivery medical instrument, such asa bipolar medical instrument. As such, the medical instrument 700includes electrical cable segments 790, 792 in addition to the pull wiresegments discussed above. The electrical cable segments 790, 792 extendthrough the wrist 710 and can be connected to the first and second jawmembers 756, 758 to energize the first and second jaw members 756, 758.Although the medical instrument 700 is illustrated as a bipolar energydelivery medical instrument that includes two electrical cable segments790, 792 energizing both the first and second jaw members 756, 758, inother embodiments, the medical instrument 700 can be a monopolar energydelivery medical instrument including a single electrical cable segment790 for energizing one of the jaw members 756, 758. Further, in someembodiments, the medical instrument 700 need not be an energy deliverydevice, and as such the electrical cable segments 790, 792 can beomitted.

Another advantage of the architecture of the medical instrument 700,including the preferred cable paths for the first and third pull wiresegments 732, 736, is that this architecture can advantageously providespace within the wrist 710 to accommodate the electrical cable segments790, 792. Since, in some embodiments, the medical instrument 700 isconfigured as a tool for laparoscopic surgery, the diameter of themedical instrument 700 should be minimized. As such, it can be difficultto provide an architecture that accommodates the additional electricalcable segments 790, 792 for energizing the jaw members 756, 758. Theaddition of the electrical cable segments 790, 792 for energizing thejaw members 756, 758 can add an additional constraint on the wristdesign. For example, the electrical segments 790, 792 can be generallystiff (e.g., when compared with the pull wires 730). This can createdifficulties for feeding the electrical cable segments 790, 792 throughthe wrist 710.

In some embodiments, to facilitate feeding the electrical cable segments790, 792 through the wrist 710, the electrical cable segments 790, 792can be mechanically coupled and slaved to one or more of the pull wires730. For example, the electrical cable segments 790, 792 can bemechanically coupled to one of the pull wire segments at two pointsalong the pull wire segments (e.g., by the jaw member and within theshaft of the medical instrument). In some embodiments, mechanicallycoupling the electrical cable segments 790 to the pull wires 730 can beaccomplished with a heat shrinking that adheres the electrical cablesegment 790, 792 to the pull wire 730. In the illustrated embodiment,the electrical cable segments 790, 792 are mechanically coupled orslaved to the pull wire segments associated with closing the jaw members756, 758. For example, the first electrical cable segment 790 can bemechanically coupled to the first pull wire segment 732, and the secondelectrical cable segment 792 can be mechanically coupled to the secondpull wire segment 734. Accordingly, the medical instrument 700 caninclude pulleys for the electrical cable segments 790, 792 that are inproximity (e.g., close to or next to) the pulleys on which the first andthird pull wire segments 732, 736 are engaged, as described below. Insome embodiments, the pulleys for the electrical cable segments 790, 792and the pulleys for the first and third pull wire segments 732, 736should be roughly the same diameter so that when the electrical cablesegments 790, 792 are mechanically coupled to the first and third pullwire segments 732, 736, the slack path lengths through wrist motionremain matched (see FIG. 29, described below).

FIG. 28 illustrates a cross-sectional view of the medical instrument 700taken at the axis of the axle 766. In this cross-sectional view, therelative positions of the first and third pull wire segments 732, 736and the electrical cable segments 790, 792 are shown for the illustratedembodiment. As illustrated, the first pull wire segment 732 ispositioned adjacent to the electrical cable segment 790, and the thirdpull wire segment 732 is positioned adjacent to the electrical cablesegment 792. This can facilitate the mechanical coupling between thefirst pull wire segment 732 and the electrical cable segment 790, aswell as the mechanical coupling between the third pull wire segment 732and the electrical cable segment 792.

Also shown in FIG. 28, in some embodiments, while the first and thirdpull wire segments 732, 736 can be positioned on the first outerproximal pulley 742 and the second outer proximal pulley 746,respectively, the first and second electrical cable segments 790, 792can be routed over the first distal clevis support leg 770 and thesecond distal clevis support leg 772, respectively. Such an arrangementmay advantageously save space within the wrist 710 as additional pulleysfor the electrical cable segments 790, 792 need not be included on theaxis 766. Such an arrangement advantageously makes use of the existingstructure of the distal clevis 724 for routing the electrical cablesegments 790, 792.

The cross-sectional view of FIG. 28 illustrates the medical instrument700 looking toward the distal end of the instrument. From this view, onecan see how the first and third pull wire segments 732, 736 extendsubstantially in alignment with the longitudinal or central axis of themedical instrument 700. As shown, from the proximal pulleys 740 towardthe distal pulleys 750, the first and third pull wire segments 732, 736extend with only a small fleet angle (e.g., less than 10 degrees or lessthan 5 degrees), as described with more detail below with reference toFIG. 35.

FIG. 29 is a top view of the medical instrument 700. In this view, thefirst and second jaw members 756, 758 and the first and second distalpulleys 752, 754 are illustrated. In this view, one can also see how thediameters for the first and second distal pulleys 752, 754 are roughlythe same where the first and third pull wire segments 732, 736 arereceived and where the electrical cable segments 790, 792 are received.As mentioned previously, providing a configuration the first and seconddistal pulleys 752, 754 with similar diameters for the first and thirdpull wire segments 732, 736 and the electrical cable segments 790, 792,can help to maintain the slack path lengths through the wrist 710.

FIGS. 30A and 30B are views of the proximal and distal pulleys of themedical instrument 700. The views are oriented looking from the proximalside of the instrument toward the distal side of the instrument. In FIG.30A, the first and second outer proximal pulleys 742, 746 and first andsecond distal pulleys 752, 754 are illustrated. FIG. 30B additionallyillustrates the first and second inner proximal pulleys 744, 748.

In the illustrated embodiment, the first and second outer proximalpulleys 742, 746 each include a groove 782, 786, which can be a singlegroove. The grooves 782, 786 can be configure to receive the first andthird pull wire segments 732, 736, such that the first and third pullwire segments 732, 736 are engaged with the first and second outerproximal pulleys 742, 746 through the grooves 782, 786. As illustrated,the first and second distal pulleys 752, 754 each comprise two grooves.For example, the first distal pulley 752 comprises a first groove 783and a second groove 785. The first groove 783 can be configured toengage the first pull wire segment 732 and the second groove 785 can beconfigured to engage the first electrical cable segment 790. Thus, thefirst pull wire segment 732 and the first electrical cable segment 790can engage with the first distal pulley 752 through the first and secondgrooves 783, 785. The diameter of the first distal pulley 752 at thefirst and second grooves 783, 785 can be substantially equal to managethe slack of the cables through the wrist as mentioned above. Similarly,the second distal pulley 754 comprises a first groove 787 and a secondgroove 789. The first groove 787 can be configured to engage the thirdpull wire segment 736 and the second groove 789 can be configured toengage the second electrical cable segment 792. Thus, the third pullwire segment 736 and the second electrical cable segment 792 can engagewith the second distal pulley 754 through the first and second grooves787, 789. The diameter of the second distal pulley 754 at the first andsecond grooves 787, 789 can be substantially equal to manage the slackof the cables through the wrist as mentioned above.

In some embodiments, the first and second grooves of the first andsecond distal pulleys 752, 754 can be separated, such that the twogrooved first and second distal pulleys 752, 754 can be replaced withfour single groove pulleys.

As shown in FIG. 30A, the first and second outer proximal pulleys 742,746 can be positioned laterally spaced apart. This configuration can beadvantageous as it may allow the first and third pull wire segments 732,736 to extend between the proximal pulleys and the distal pulleys inalong a path length that is substantially aligned with a longitudinal orcenter axis of the wrist 710. For example, as shown in FIG. 30A, thefirst pull wire segment 732 extends between the first outer proximalpulley 742 and the first distal pulley 752 and the third pull wiresegment 736 extends between the second outer proximal pulley 746 and thesecond distal pulley 754 in the areas circled with dotted lines.Notably, in these areas, the first outer proximal pulley 742 can benearly aligned with the first groove 783 of the first distal pulley 752and the second outer proximal pulley 746 can be nearly aligned with thefirst groove 787 of the second distal pulley 754.

FIG. 30B additionally illustrates the relative position of the innerproximal pulleys 744, 748. As shown, the inner proximal pulleys 744, 748can be positioned toward the center of the medical instrument 700. Thiscan provide spaces 799 between the inner and outer proximal pulleys asshown. The spaces 799 can be configured to receive the first distalclevis support leg 770 and the second distal clevis support leg 772 asshown in FIG. 28. Positioning the first distal clevis support leg 770and the second distal clevis support leg 772 in the spaces 799 betweenthe inner and outer proximal pulleys can help to create the nearalignment as discussed above, as well as facilitate the routing of theelectrical cable segments 790, 792. Further, this arrangement allows theelectrical cable segments 790, 792 to be routed over the first distalclevis support leg 770 and the second distal clevis support leg 772 asmentioned above, and as described further below with reference to FIGS.31, 32, and 33.

FIG. 31 is a first side view of the medical instrument 700. FIG. 32 is asecond side view of the medical instrument 700. FIG. 33 is across-sectional side view of the medical instrument 700. As shown inFIG. 31 (see also FIG. 28), the first distal clevis support leg 770 canbe positioned between the outer proximal pulley 742 and the innerproximal pulley 744 and the second distal clevis support leg 772 can bepositioned between the outer proximal pulley 746 and the inner proximalpulley 748. This can space the outer proximal pulleys 742, 746 laterallyoutward to allow the alignment discussed above with reference to FIG.30A.

Further, as shown, the electrical cable segment 790 can be routed aroundthe first distal clevis support leg 770. Although not visible in FIG.31, the electrical cable segment 792 can be similarly routed around thesecond distal clevis support leg 772 on the opposite side of the medicalinstrument 700. In some embodiments, the first and second distal clevissupport legs 770, 772 can be shaped into a static redirect surfaces forredirected the electrical cable segments 790, 792 around the axle 766(e.g., around the pitch axis).

As best seen in the cross-sectional view of FIG. 33, the stationaryredirect surfaces on the first distal clevis support leg 770 and thesecond distal clevis support leg 772 can be joined by correspondingstationary redirect surfaces 795 in the proximal clevis 722. While insome embodiments it may be preferred to have a dynamic redirect surface(e.g., pulley) for the electrical cable segments 790, 792, there can belimited space to fit additional pulleys within the wrist 710.Accordingly, the illustrated architecture advantageously fits theelectrical cable segments 790, 792 such that they are routed on top ofexisting structural members. Further, the electrical cable segments 790,792 may not experience as high tension loads as the pull wire segments.As such, use of static redirect surfaces for the electrical cablesegments 790, 792 can be tolerable, and even preferable given the spacerestraints for the wrist 710.

As shown in FIGS. 31-32, the medical instrument 700 can also includeshaft redirect pulleys 760 positioned in the proximal clevis 722 and/orwithin the elongated shaft. FIG. 34 is a cross-sectional view of themedical instrument 700 taken through the shaft redirect pulleys 760. Asshown in FIG. 34, the shaft redirect pulleys 760 can include a firstouter shaft redirect pulley 762, a first inner shaft redirect pulley764, a second outer shaft redirect pulley 766, and second inner shaftredirect pulley 768. In the illustrated embodiment, the shaft redirectpulleys 760 are in a staggered position. That is, as shown in FIG. 34,the first outer shaft redirect pulley 762 is positioned on first axis763 and the first inner shaft redirect pulley 764 is positioned onsecond axis 765. The first and second axes 763, 765 are not coaxial (inthe illustrated embodiment). The second inner shaft redirect pulley 768is positioned on a third axis 769. In the illustrated embodiment thethird axis 769 is coaxial with second axis 765. The second outer shaftredirect pulley 766 is positioned on fourth axis 767. In the illustratedembodiment, the fourth axis 767 is not coaxial with the first, second,or third axes 763, 768, 769.

FIG. 34 further illustrates engagement of the first, second, third, andfourth pull wire segments 732, 734, 736, 738 with the shaft redirectpulleys 760, as well as the positions of the electrical cable segments790, 792. In this view, engagement between the redirect surfaces 795 ofthe proximal clevis 722 and the electrical cable segments 790, 792 canbe seen.

FIG. 35 is a diagram illustrating a preferential cable path 705 betweenthe proximal pulleys 740 and the distal pulleys 750. As shown, thepreferential cable path 705 can be nearly aligned with a longitudinal orcentral axis 703 of the medical instrument 700. For example, an anglebetween the longitudinal or central axis 703 and the preferential cablepath 705 can be less than 10 degrees or less than 5 degrees in each oftwo orthogonal planes (e.g., the pitch plane and the yaw plane). In theillustrated diagram, example angles are shown at 3.93 degrees and 4.35degrees in each of the two orthogonal planes.

3. Implementing Systems and Terminology

Implementations disclosed herein provide systems, methods and apparatusfor medical instruments including wrists with hybrid redirect surfaces.

It should be noted that the terms “couple,” “coupling,” “coupled” orother variations of the word couple as used herein may indicate eitheran indirect connection or a direct connection. For example, if a firstcomponent is “coupled” to a second component, the first component may beeither indirectly connected to the second component via anothercomponent or directly connected to the second component.

The phrases referencing specific computer-implementedprocesses/functions described herein may be stored as one or moreinstructions on a processor-readable or computer-readable medium. Theterm “computer-readable medium” refers to any available medium that canbe accessed by a computer or processor. By way of example, and notlimitation, such a medium may comprise random access memory (RAM),read-only memory (ROM), electrically erasable programmable read-onlymemory (EEPROM), flash memory, compact disc read-only memory (CD-ROM) orother optical disk storage, magnetic disk storage or other magneticstorage devices, or any other medium that can be used to store desiredprogram code in the form of instructions or data structures and that canbe accessed by a computer. It should be noted that a computer-readablemedium may be tangible and non-transitory. As used herein, the term“code” may refer to software, instructions, code or data that is/areexecutable by a computing device or processor.

The methods disclosed herein comprise one or more steps or actions forachieving the described method. The method steps and/or actions may beinterchanged with one another without departing from the scope of theclaims. In other words, unless a specific order of steps or actions isrequired for proper operation of the method that is being described, theorder and/or use of specific steps and/or actions may be modifiedwithout departing from the scope of the claims.

As used herein, the term “plurality” denotes two or more. For example, aplurality of components indicates two or more components. The term“determining” encompasses a wide variety of actions and, therefore,“determining” can include calculating, computing, processing, deriving,investigating, looking up (e.g., looking up in a table, a database oranother data structure), ascertaining and the like. Also, “determining”can include receiving (e.g., receiving information), accessing (e.g.,accessing data in a memory) and the like. Also, “determining” caninclude resolving, selecting, choosing, establishing and the like.

The phrase “based on” does not mean “based only on,” unless expresslyspecified otherwise. In other words, the phrase “based on” describesboth “based only on” and “based at least on.”

The previous description of the disclosed implementations is provided toenable any person skilled in the art to make or use the presentinvention. Various modifications to these implementations will bereadily apparent to those skilled in the art, and the generic principlesdefined herein may be applied to other implementations without departingfrom the scope of the invention. For example, it will be appreciatedthat one of ordinary skill in the art will be able to employ a numbercorresponding alternative and equivalent structural details, such asequivalent ways of fastening, mounting, coupling, or engaging toolcomponents, equivalent mechanisms for producing particular actuationmotions, and equivalent mechanisms for delivering electrical energy.Thus, the present invention is not intended to be limited to theimplementations shown herein but is to be accorded the widest scopeconsistent with the principles and novel features disclosed herein.

What is claimed is:
 1. A medical instrument, comprising: a shaft extending between a proximal end and a distal end; a wrist positioned at the distal end of the shaft, the wrist comprising: a proximal clevis connected to the distal end of the shaft, a distal clevis pivotally connected to the proximal clevis, the distal clevis configured to rotate about a pitch axis, a plurality of proximal pulleys configured to rotate about the pitch axis, and a plurality of distal pulleys configured to rotate about a yaw axis; and an end effector connected to the plurality of distal pulleys; a plurality of pull wires engaged with the plurality of proximal pulleys and the plurality of distal pulleys and configured to articulate the wrist and actuate the end effector, wherein the plurality of pull wires comprise at least: a first pull wire segment having a first cable path length extending between a first proximal pulley of the plurality of proximal pulleys and a first distal pulley of the plurality of distal pulleys, and a second pull wire segment having a second cable path length extending between a second proximal pulley of the plurality of proximal pulleys and the first distal pulley, wherein the first cable path length is less than the second cable path length.
 2. The instrument of claim 1, wherein the end effector comprises: a first jaw member connected to the first distal pulley; and a second jaw member connected to a second distal pulley of the plurality of distal pulleys.
 3. The instrument of claim 2, wherein actuation of the first pull wire segment causes rotation of the first jaw member in a first direction to open the end effector.
 4. The instrument of claim 3, wherein actuation of the second pull wire segment causes rotation of the second jaw member in a second direction to close the end effector.
 5. The instrument of claim 2, wherein the first pull wire segment extends between the first proximal pulley and the first distal pulley without contacting the distal clevis.
 6. The instrument of claim 5, wherein the first pull wire segment extends substantially parallel to a longitudinal axis of the wrist.
 7. The instrument of claim 5, wherein the first pull wire segment extends at an angle of less than 10 degrees relative to a longitudinal axis of the wrist.
 8. The instrument of claim 5, wherein the second pull wire segment contacts a redirect surface of the distal clevis between the second proximal pulley and the first distal pulley.
 9. The instrument of claim 8, wherein the redirect surface comprises a static surface of the distal clevis.
 10. The instrument of claim 1, further comprising a conductive cable extending through the wrist to the end effector, wherein the conductive cable is configured to extend over a second redirect surface of the distal clevis.
 11. The instrument of claim 10, wherein the second redirect surface of the distal clevis comprises a support leg of the distal clevis.
 12. The instrument of claim 11, wherein the support leg is positioned between at least two of the plurality of proximal pulleys.
 13. The instrument of claim 10, wherein the conductive cable is coupled to the first pull wire segment.
 14. The instrument of claim 10, wherein the end effector comprises a bipolar end effector and the conductive cable is coupled to a jaw member of the end effector to energize the jaw member.
 15. A medical instrument, comprising: a shaft extending between a proximal end and a distal end; a wrist positioned at the distal end of the shaft, the wrist comprising: a proximal clevis connected to the distal end of the shaft, a distal clevis pivotally connected to the proximal clevis, the distal clevis configured to rotate about a pitch axis, a plurality of proximal pulleys configured to rotate about the pitch axis, and a plurality of distal pulleys configured to rotate about a yaw axis; and an end effector connected to the plurality of distal pulleys; a plurality of pull wires engaged with the plurality of proximal pulleys and the plurality of distal pulleys and configured to articulate the wrist and actuate the end effector, wherein the plurality of pull wires comprise at least: a first pull wire segment extending between a first proximal pulley of the plurality of proximal pulleys and a first distal pulley of the plurality of distal pulleys without contacting the distal clevis, and a second pull wire segment extending between a second proximal pulley of the plurality of proximal pulleys and the first distal pulley, the second pull wire segment contacting a redirect surface of the distal clevis.
 16. The instrument of claim 15, wherein the end effector comprises: a first jaw member connected to the first distal pulley; and a second jaw member connected to a second distal pulley of the plurality of distal pulleys.
 17. The instrument of claim 16, wherein actuation of the first pull wire segment causes rotation of the first jaw member in a first direction to open the end effector.
 18. The instrument of claim 17, wherein actuation of the second pull wire segment causes rotation of the second jaw member in a second direction to close the end effector.
 19. The instrument of claim 15, wherein the first pull wire segment extends substantially parallel to a longitudinal axis of the wrist.
 20. The instrument of claim 15, wherein the first pull wire segment extends at an angle of less than 10 degrees relative to a longitudinal axis of the wrist. 